Port seeded Age completion and Accelerated pages to 26.3 beta

README.md

@@ -15,11 +15,12 @@ incomplete **Minecraft 26.3 beta** is available: Java 25, NeoForge 26.3.0.99,
 and a first-party Age backend (no Dynamic Dimensions or Bad Packets). It now
 supports authored terrain/biomes, structure and vegetation pages, independent
 Age weather/lighting, seeded and colorable Overworld/Nether/End/Static skies,
-Normal Time length/phase/direction/bearing and sun-size controls,
-and a growing set of generation features,
-but does not yet provide full 1.21.1 gameplay or optional-integration parity.
+independent Sun/Moon controls, multiple bodies and eclipses, seeded biome and
+feature completion, and random structure selection. Nether/End noise-biome
+materials now follow their native rules. The beta does not yet provide full
+1.21.1 gameplay or optional-integration parity.
 See the [26.3 beta guide](ports/mc263/README.md) and
-[latest beta release notes](ports/mc263/RELEASE_NOTES_1.0.1.78-beta.1.md).
+[latest beta release notes](ports/mc263/RELEASE_NOTES_1.0.1.98-beta.1.md).
 Keep the builds and their saves separate, and back up worlds before updating.
 
 ## Getting started

docs/MINECRAFT_26_3_PORT.md

@@ -10,6 +10,17 @@ tracks issues #97–#103 under parent #96.
 
 ## Version boundary
 
+Local slice `1.0.1.98-beta.1` ports the 1.21.1 Accelerated environment page:
+stacking extra random block ticks in already-loaded player-nearby chunks,
+eight-chunk/16,384-attempt default budgets, fair rotating section allocation,
+and an Age-local saved page count. The 26.3 LOCAL config holds these limits.
+Entities, machines and scheduled ticks are unaffected. Existing Ages remain
+unaccelerated; random Age inclusion and instability scoring are not added.
+The suspected host-seed biome zoom mismatch was checked against NeoForge's
+patched ServerLevel constructor: seedOverride already replaces it correctly,
+so the backend seed path was left unchanged. Native Cave policy issue #111
+remains separate future work for both Minecraft tracks.
+
 Minecraft 26.3/NeoForge uses Java 25, while Rivencraft 1.21.1 uses Java 21.
 Build and publish separate artifacts; do not widen the Minecraft dependency
 range of the 1.21.1 JAR. The official [26.3 release notes](https://www.minecraft.net/en-us/article/minecraft-java-edition-26-3),
@@ -1303,6 +1314,642 @@ unchanged moon, and travel isolation still require the user's client check.
 The server stopped cleanly and its temporary world was deleted. Nothing is
 committed, pushed or published without an explicit request.
 
+## Normal Time shared celestial color
+
+`1.0.1.79-beta.1` ports the root `AgeSkyProfile` behavior that consumes a
+pending shared color group at Normal Time and applies it to both paired
+bodies. `PortAgeColors` now saves an optional `celestial` RGB value, default
+-1 (native/untinted), with catalog protocol 7 for synchronization. Existing
+sky/ambient fields and old profiles retain their values. Color accumulation
+passes through non-color celestial modifiers, clamps at the target, resets
+after consumption, and leaves trailing colors assigned to sky as before.
+
+Extraction copies the saved tint into `SkyRenderState`. A narrowly scoped
+native sun/moon uniform modification multiplies RGB while retaining alpha;
+there are no live world reads during drawing, new textures, pipelines or GPU
+buffers. Native weather fading, transparent halos, moon phases, stars and
+sunrise glow remain unchanged. Time and effective illumination are not tied
+to RGB. State reset/defaults prevent cross-dimension tint leakage. Independent
+Sun/Moon pages, multiple bodies and per-body colors remain unported.
+
+The `create_celestial_color` fixture checks three separate target groups,
+completed-group clamping, modifier passthrough, consumed-group reset, seeded
+unnumbered colors, old codec defaults and catalog round trips. Client checks
+must cover a frozen Zenith sun, Nadir moon, mixed colors, transparent halos,
+restart and return to an untinted dimension. Server probes validate saved
+profiles and attributes, not rendered output. Build passed; disposable-server
+fixtures retained separate sky/ambient/body colors through reload, reseed and
+restart, including zero/black colors and untouched native defaults. Sampled
+time/light remained unchanged. The server stopped cleanly and its temporary
+world was deleted. No commit/push/publication is performed without an explicit
+request.
+
+## Standalone Sun and Moon controllers
+
+`1.0.1.80-beta.1` extends the existing cycle profile with optional `body_mode`
+(paired=0, Sun=1, Moon=2); old profiles default to the paired renderer.
+Catalog protocol 8 includes this field. One celestial controller is accepted
+per book, with existing Length/Phase/Direction/Angle/Size and shared Color
+groups. Multiple controllers and dangling/duplicate modifiers retain the
+interim strict rejection rather than losing written pages.
+
+Standalone bodies use a linear angular orbit as in root `AgeSkyProfile.Body`.
+Both native body-angle attributes point at that orbit; render-state mode
+suppresses the absent counterpart. The selected Moon consumes Size itself;
+Normal Time retains its original sun-only sizing. Moon-only sunrise glow is
+suppressed before any horizon pose is pushed. Shared RGB/alpha handling and
+native buffers/pipelines are reused, with extraction/reset defaults protecting
+other dimensions. Missing Sky completion uses Overworld, as before. Explicit
+Nether/End/Static still does not draw bodies in this native-renderer slice.
+
+The gameplay skylight attribute follows root `lightAt` and
+`LevelSkyBrightnessMixin`: positive cosine altitude, 0.18 for a moon, weather
+attenuation, then the 11-level sky-darkening range. It does not infer light
+from color or size, and does not bypass Bright/Dark or no-skylight terrain.
+Native background/star/moon-phase schedules remain, rather than claiming a
+full custom sky port. Seeded default phase/bearing completion, multiple
+independent bodies and eclipses remain future work.
+
+The op `create_body` fixture checks all named phases for both bodies, light
+weights, numeric size, reverse motion, order rejection, old-profile defaults,
+compatible missing Sky and catalog synchronization. Actual body visibility,
+moon size, glow transparency and travel isolation require manual client
+validation. Build and disposable-server probes passed: Zenith sun/moon
+skylight was 15/6, Nadir and horizon were 4; named phase angles were correct.
+The paired fixture retained its opposite moon and native lighting. Reload,
+reseed and full restart preserved body mode, color, size, bearing and phase.
+The test server stopped and its temporary world was deleted. No commit/push/
+publication is performed without an explicit request.
+
+## Multiple independent authored celestials
+
+`1.0.1.81-beta.1` adds an optional immutable `PortCelestialBody` list to the
+cycle profile and catalog protocol 9. Existing profiles default to an empty
+list and use their validated native paired/single path. Books with multiple
+controllers compile ordered modifier groups into independent body orbits;
+Normal Time expands into opposite-phase sun/moon entries. Colors are consumed
+at each controller, with original page indices retained for seeded amounts.
+Uncolored bodies reset to native white rather than inheriting the previous
+body's tint. Size/phase/length/bearing/direction also reset per group.
+
+The profile constructor and authoring gate enforce the root ten-sun/ten-moon
+limit, with Normal Time counting toward both. Duplicate modifiers within a
+group and dangling modifiers remain strict errors until grammar recovery is
+ported. The first controller continues to govern the shared day timeline and
+native background/star/moon-phase schedules. Positive-altitude sunlight sums
+to at most 1; only if no sunlight contributes is summed 0.18-weight moonlight
+used. Weather and Bright/Dark remain separate. No eclipse attenuation is
+included yet.
+
+Extraction resolves body angles into immutable presentation snapshots. The
+native body pass is replaced only for a nonempty multi-body list: draw suns
+first, then moons with their own color, size and bearing, then native stars
+once. Native buffers, pipelines and alpha are reused. Temporary renderer
+parameters and pose transforms restore in finally blocks; no world lookup is
+performed during drawing. Explicit Nether/End/Static rendering remains a
+separate limitation. Eclipse disc occlusion, corona and sky/light attenuation
+will be the following slice, not a claim of this implementation.
+
+`create_celestials` checks independent motion/color/size, modifier reset, Normal
+Time expansion, ten-pair acceptance/overflow rejection, profile codecs and
+catalog round trips. Manual checks cover body placement/alpha, multiple
+controllers, restart and ordinary-dimension isolation. Build passed, as did
+disposable-server profile/catalog checks, combined-light invariants, reload,
+reseed and full restart. Single-body, paired and tinted fixtures retained
+their earlier behavior. The test server stopped and its temporary world was
+deleted. No commit/push/release is performed without explicit instruction.
+
+## Eclipse effects
+
+`1.0.1.82-beta.1` adapts root `AgeSkyProfile.eclipseFor`, `eclipseAt` and
+`lightAt`, plus `RivencraftSkyEffects.drawBody`. The dot-product separation
+of normalized orbit directions is compared with the sum of quarter-disc
+angular radii; each body takes the strongest opposite-kind contact. This is
+root's radial proximity formula, not a new physical disc-area model. Bearing,
+phase, size, motion and direction all affect contact. Same-kind and isolated
+bodies have no eclipse; only an above-horizon sun contributes global shading.
+
+Sunlight is multiplied by `1 - 0.85 * overlap` before the existing light
+aggregation and weather handling. Extraction shades sky RGB by
+`1 - 0.65 * strongestVisibleSolarOverlap`. Moon RGB scales by `1 - overlap`;
+sun RGB moves toward white by `pow(overlap, 8) * 0.8`. Values are derived from
+saved profiles, requiring neither a new saved schema nor packet fields.
+Existing multi-body Ages gain the effects on update; single/paired native
+paths stay unchanged. Overlap calculations are bounded by the 20-body limit,
+and extracted presentation values are reused without live-world drawing reads.
+
+Native transparent glows draw before each body's central ordinary-alpha disc.
+A registered pipeline cloned from native Celestial uses conventional alpha
+blending; cached center-cropped atlas meshes retain native UV orientation.
+An eclipsed moon uses the full-moon core to avoid transparent phase pixels
+exposing the sun (root always drew that full-moon center). Weather alpha is
+retained. The helper drops meshes on atlas-generation change and closes them
+with the renderer. There is no generated art or per-frame mesh allocation.
+Explicit Nether/End/Static body rendering remains outside this slice.
+
+`create_eclipse` supplies aligned, partial, clear, below-horizon and moving
+fixtures; it checks overlap/color/light constants, same-kind exclusion and
+motion out of contact. The multi-body op fixture is renamed
+`create_celestials` to avoid merging with the unrelated existing terrain
+`create_multi` command. Manual checks must confirm disc opacity, halo,
+corona/sky darkening, resource reload and travel isolation. Build passed.
+Disposable-server fixtures passed with overlap 1/0.293/0 for aligned/partial/
+clear cases and no global shading for below-horizon alignment. Aligned
+sunlight was 0.15, clear sunlight 1; sampled skylight was 6/12/15 for aligned/
+partial/clear. Moving contact ended as expected. Reload, reseed, catalog
+round trips and full restart retained profiles and derived light behavior;
+earlier standalone/paired fixtures remained unchanged. The test server stopped
+and its temporary world was deleted. No commit/push/publication is performed
+without an explicit request.
+
+## Authored moon sprite correction
+
+`1.0.1.83-beta.1` removes the mixed native-phase/full-core adaptation introduced
+with the opaque eclipse pass. Standalone and multi-body authored moons now
+draw full-moon glow and center consistently, matching root's custom renderer,
+which always samples the first (full-moon) atlas cell. Under ordinary alpha,
+native dark phase pixels can produce black opaque centers; the old overlay
+glow had made those dark pixels effectively invisible. The ordinary native
+Normal Time pair retains its calendar phases. No eclipse math, saved profile,
+catalog protocol or world data changes are needed.
+
+The user's `celest` Age was read without modification. Its body colors are
+all -1 (native white), not corrupted black values. Its first Moon and second
+Sun both have period 1, phase 0, origin 0, clockwise direction and native
+bearing -1; they remain exactly coincident. That moon's full eclipse and its
+occlusion of the sun are expected under the newly added root overlap rules,
+independent of the phase-sprite correction. Do not silently alter player-authored
+orbits to conceal the intentional alignment. Manual checks cover nonaligned
+moons, the known permanent eclipse, Native Normal Time, resource reload and
+cross-dimension isolation. No user save was modified, and nothing is committed,
+pushed or published without explicit instruction.
+
+## Celestials over explicit non-Overworld skies
+
+`1.0.1.84-beta.1` removes the presentation exclusion that hid authored bodies
+over Nether/End/Static. Root `RivencraftSkyEffects` draws its body list after
+any chosen background. The native 26.3 paths instead returned after End or
+skipped a NONE sky entirely. An extracted overlay-mode flag now schedules an
+authored body layer without changing the actual dimension type or gameplay.
+Single Sun/Moon and Normal Time profiles expand into temporary presentation
+bodies on these backgrounds; saved profiles are not rewritten. Existing
+Overworld single/paired/multi-body paths stay unchanged.
+
+End uses a RETURN hook that includes the native early return, after its pass
+is closed. Static closes its own background pass before drawing the overlay.
+Fog-only Nether presentation schedules an extracted END sky pass, suppresses
+its End background/flash drawing, and retains the fog clear color. Overlay
+passes load existing targets without clearing, reuse native body resources
+and suppress additional stars/horizon glow on non-Overworld backgrounds.
+Weather alpha is extracted even when the native NONE/END branch omits it.
+All presentation flags reset when the render state is reused.
+
+Eclipse shading modulates End/Static background tint; Nether-style fog color
+uses the same root shade factor through an environment attribute layer.
+Native untinted fog and authored sky colors are both supported; other
+backgrounds retain their existing fog behavior. Body lighting and eclipse
+geometry do not depend on style. Missing Sky selection still chooses
+Overworld for authored celestials. No schema/protocol changes or new assets
+are required. The eclipse fixture accepts an optional explicit Sky; server
+checks cover saved choices, fog/light behavior and persistence, while visual
+layering, no duplication, resource reload and travel isolation require manual
+client checks. Build and disposable-server checks passed for all four sky
+styles: aligned eclipse skylight stayed 6, clear stayed 15, and Nether fog
+scaled by 0.35 only during overlap. No-celestial and tinted-Nether fixtures
+retained their expected colors. Saved profiles, style, light and fog survived
+reload/reseed and full restart. The test server stopped and its temporary
+world was deleted. No commit/push/publication is performed without explicit
+request.
+
+## Bare celestial seeded randomization
+
+`1.0.1.85-beta.1` adds per-controller randomization specifically for bare
+Sun/Moon groups, as requested for easier testing. This deliberately uses the
+root **random-Age** ranges rather than its authored compile defaults (which
+reuse shared seeded phase/bearing and default size/color). A dedicated stream
+mixes Age seed with controller ordinal, independent of unrelated page indices,
+terrain/weather/lighting RNG and sky selection. Palette/mixing and 0.75–1.75
+size come from `AgeSkyProfile.random`; 0.2–2 periods with 1/7 stopped chance
+come from `AgeTraits.select`. Bearing and phase use the port's existing degree/
+tick granularity. Direction is random per body. Counts and body-kind limits
+still follow explicitly written controller pages.
+
+The compiler recognizes whether a controller has any written celestial
+modifier. Colors already consumed by Sky/Ambient do not suppress randomization.
+Any written celestial modifier retains the previous authored path as a whole,
+not just individual field overrides; partially authored groups do not gain
+new random missing fields in this slice. Normal Time and absent controllers
+are unchanged. Bare controllers materialize immutable full body profiles,
+including a one-body list for standalone cases. Multi-body compilation carries
+their colors/orbits without replacing them with native defaults. No new
+saved schema, protocol or client renderer code is needed.
+
+Only newly created Ages compile these defaults. Older saved profiles load
+unchanged; GUI opening, restart and terrain reseeding do not reroll them.
+`create_random_celestials` checks reproducibility, ordinal independence,
+unrelated-page stability, 128-seed bounds/pool coverage and unchanged authored/
+Normal Time behavior. The regular fixtures still exercise explicit groups.
+Manual checks cover visible variation, moving/stopped bodies, mixed authored
+groups and restart. Build and disposable-server checks passed, including
+single bare bodies, multi-body/128-seed coverage, catalog round trips,
+unrelated-page stability, explicit/eclipsed fixtures, reload, terrain reseed
+and full restart. Saved random parameters remained unchanged while moving
+orbits continued with the clock. The server stopped and its temporary world
+was deleted. No commit/push/publication occurs without explicit request.
+
+## Missing celestial branch completion
+
+`1.0.1.86-beta.1` adds creation-only `PortDayCycle.resolve`. Written controllers
+delegate to the validated compiler unchanged. If none exist, the root
+`AgeSkyProfile.random` draw positions select 0–3 suns and 0–3 moons: consume
+the sky-style draw and mixed sky-color draws, then the two counts. Body
+settings reuse .85's independent per-controller streams. This matches root's
+unrestricted count model, not bit-identical per-body values; the .85 per-body
+length/direction independence is retained. Missing sky tint completion and
+random-page policy parity are not claimed by this slice.
+
+The shared resolver is used by player book creation and the `create_random`
+operator command. Other exact diagnostic fixtures continue using `compile`
+or native profiles to isolate their subject. A saved NONE body mode (3)
+represents a resolved zero-body sky. Its sun/moon/horizon drawing is suppressed
+without switching to Dark lighting or changing the native background/star
+timeline. Old missing profiles still decode to NATIVE rather than being
+retroactively completed. The mode-domain extension uses catalog protocol 10.
+No generation runs or rerolls happen during GUI rendering, load or reseed.
+
+`create_completed_sky` tests 256-seed count bounds and coverage of empty,
+sun-only, moon-only and mixed results; reproducibility and unrelated-page
+stability; explicit-controller precedence; old defaults; and catalog round
+trips. Manual checks cover varied new books, empty skies, explicit-controller
+counts, all backgrounds, restart and Overworld isolation. No commit/push/
+publication is performed without explicit instruction.
+
+The .86 build and disposable dedicated-server checks passed: four background
+fixtures, the seed-14 empty sky, random Age creation, explicit controllers,
+catalog round trips, unload/reload, terrain reseeding and full restart. Saved
+body parameters survived unchanged. The test server was stopped and its world
+deleted; client visual confirmation remains a manual check.
+
+## Random Age sky-color completion
+
+`1.0.1.87-beta.1` uses creation-only `PortAgeColors.resolve` for player books
+and `age create_random`. Empty symbol lists choose a sky tint from root
+`AgeSkyProfile.random`'s palette and draw order, including its rounded channel
+averages. Nonempty symbol lists delegate to the existing compiler unchanged.
+This intentionally distinguishes wholly random Ages from authored books with
+an omitted sky-color branch, as 1.21.1 does. The existing .85 per-body random
+color truncation is preserved by a shared palette helper; celestial count and
+body random streams do not change.
+
+Colors are stored in the existing profile and catalog fields. Old native
+colors are not retroactively randomized; reload, restart and terrain reseed
+do not rerun completion. No protocol update is necessary. The completed-sky
+diagnostic checks six root seed/color vectors, codec persistence, authored
+precedence (including explicit black) and old-profile defaults. Random-page
+blocklist parity remains separate pending work.
+
+Build and disposable dedicated-server checks passed: root vectors and authored
+precedence, color attributes/catalog round trips for all four background
+styles, explicit sky/ambient colors, unload/reload, reseed and full restart.
+Saved random colors stayed unchanged after reseeding and restart. The test
+server was stopped and its disposable world deleted. Client rendering is
+still a manual check. No commit, push or publication was performed.
+
+## Authored biome branch completion
+
+`1.0.1.88-beta.1` ports the explicit-controller missing-pool behavior from
+1.21.1 `AgeBiomeSelection.compile`: Single requires one biome; other nonnative
+controllers require two distinct biomes. An entirely omitted pool uses the
+seeded 2:1 continuation/stop draw up to the eligible pool size. Authored pools
+fill only to the minimum, preserve order and duplicate weights, and never add
+an unrequested third biome once the minimum is met. Native still disallows
+biome pages. The binder's availability validation accepts incomplete pools;
+the server resolves actual registry eligibility before creating the Age.
+
+Player creation now passes the actual Age seed to biome compilation. Exact
+older diagnostics retain the registry-only compiler; the new completion
+fixture exercises the production seeded path. Cave uses recognized Cave and
+Nether biomes. Void does not inject The Void alongside authored biomes and
+reports a clear distinct-biome error when completion is impossible. Pools
+are stored in existing `PortBiomePlan` fields and never rerolled on restart
+or terrain reseed. No protocol change is needed. Broader writing recovery,
+structure-driven missing-biome selection and random-page policies remain
+separate parity work.
+
+The build and disposable dedicated-server checks passed. The completion
+fixture checked every distribution over 32 seeds, partial/full/weighted pools
+and codec round trips. Created Standard Single, Flat Tiny, Cave Tiny and Void
+Single plans; Cave included the new 26.3 Sulfur Caves biome. An impossible
+controller-only Void Tiny pool was refused with the distinct-biome message.
+Generator pools survived unload/reload, reseed and full server restart.
+The server was stopped and the temporary world deleted. Binder interaction
+and in-game biome layouts still require manual validation. No commit, push
+or publication was performed.
+
+## Unpaired material completion
+
+`1.0.1.89-beta.1` adapts 1.21.1 `AgeFeatureSelection.implied`. A shared pure
+normalizer expands an unpaired material into an internal material/feature
+pair, keyed by Age seed, material ID and its original book index. Rock, lake
+and terrain-feature compilers all use the same completed view. Original book
+pages stay unchanged and no random selection happens at render/load time.
+Explicit feature targets suppress completion, including incompatible targets
+that must still be rejected by the current strict grammar.
+
+Candidate ordering and terrain restrictions follow root's material-feature
+list: Rocks/Floating Islands/Tendrils/Spheres/Spikes/Obelisks for solids and
+the three lake types for fluids, filtered by supported terrain. Cave only
+permits the two terrain-independent solid features; Void also permits floating
+islands; Flat excludes Rocks. No fallback fluid feature exists on Flat, Cave
+or Void. This does not add page-free random features, nor remove the existing
+per-feature caps or introduce instability recovery. Resulting plans use their
+existing save codecs, so no catalog/protocol change is needed.
+
+The operator fixture checks 64 seeds on each terrain: independent consecutive
+materials, deterministic/idempotent completion, explicit precedence, candidate
+coverage, fluid retention and incompatible-fluid rejection. Persistence and
+actual generator plans are inspected with `feature_plan` without generating
+chunks. Client binder interaction and feature visibility remain manual checks.
+
+The .89 build and disposable server checks passed: seeded fixture assertions,
+Standard Glowstone Spikes, Cave Diamond Spheres, Void Stone Tendrils, Flat
+Glowstone Obelisks and Standard Water Deep Lakes. Cave Water was refused.
+Feature plans and materials survived unload/reload, terrain reseed and full
+restart. The server was stopped and its temporary world deleted. No commit,
+push or publication was performed.
+
+## Page-free random material features
+
+`1.0.1.90-beta.1` adapts the material and rare-formation portion of 1.21.1
+`AgeFeatureSelection.randomChoices`. A new creation-only selector shares the
+production authored plan compilers rather than duplicating generator logic.
+It rolls 0–2 unique material feature types, uses root's candidate ordering and
+Legacy rank chooser, removes chosen types, and selects full-collision solids
+or source fluids from the registered sorted pools. Terrain eligibility uses
+the current port validator. The separate seeded Skylands and Star Fissure
+rolls and the 1-in-10 Crystal Formations roll follow root's rules.
+
+Player Link-Panel-only creation and `age create_random` share this selector.
+Authored books still use their own feature compilers, including implied
+materials from .89. Plans are frozen in existing save fields, without extra
+book pages or a protocol change. Old Ages keep their original plans.
+Random structures, random-page policies and instability are not claimed by
+this slice. Material values can be valuable/hazardous, matching the root pool;
+the instability port must account for that before stable release.
+
+`create_random_features` checks 64 seeds across all terrain types: seeded
+determinism, counts 0/1/2, unique feature types, all nine candidate families,
+terrain compatibility, rare-feature coverage, and plan codec round trips.
+`feature_plan` treats an absent feature generator as a valid empty result.
+Client feature visibility remains a manual check.
+
+The .90 build and disposable server checks passed. The seeded matrix covered
+all six terrains and all nine material feature families. Created surface,
+Cave, Flat and Void fixtures, including lakes, rare Skylands and a Star
+Fissure, and verified the production `create_random` plan. Seed 0 Standard
+correctly produced no features; seed 1 produced a single lake. Saved plans
+survived unload/reload, reseed and full restart. The server was stopped and
+its temporary world deleted. Nothing was committed, pushed or published.
+
+## Page-free random structures
+
+`1.0.1.91-beta.1` ports `AgeStructureSelection.randomChoices`: an independent
+seed stream rolls 0–2 unique candidates using Legacy ranks. Terrain and
+registry availability are checked, then the selected biome pool must intersect
+the structure set's normal biome eligibility. This is deliberately stricter
+than authored pages, which retain their existing biome overrides. Native
+Flat uses Plains, Native Cave uses the backend's Lush Caves fallback, and
+other native noise terrain uses the Overworld LevelStem biome source. A
+non-Native plan uses its saved biome IDs. Abandoned Camps are added after
+the root candidate list at rank 3. Cave Dungeons remain excluded by current
+port support, whereas root permits that combination; it needs a separate
+placement validation before enabling it.
+
+The combined random feature resolver preserves .90 material/rare choices,
+adds Dungeons separately, and merges structure pages into the saved terrain
+feature plan. A new optional `structure_control` field defaults false for
+old profiles and is true for new random Ages, even for an empty selection.
+The generator applies its existing controlled-set filter when that flag is
+true. This prevents zero choices from accidentally retaining all vanilla
+controlled sets. Other native structure families still use their normal
+biome gate. Existing authored/old plans are not rewritten, and no catalog
+protocol change is needed.
+
+The operator fixture checks seeded counts/uniqueness, all terrains, fixed
+Plains/End/Nether biome pools, native defaults, biome eligibility, the empty
+controlled-set gate, explicit Village precedence, merge/codec persistence,
+and old-profile defaults. Actual placement remains an in-game check.
+
+The .91 build and disposable server checks passed. Fixtures exercised Plains,
+Native Flat, Nether-biome Cave, End-biome surface and empty Void selection,
+plus the production random-Age command. Village, Fortress and Dungeon plans,
+and an intentionally empty controlled plan, survived unload/reload, reseed
+and full restart. Namespaced biome arguments were checked. The server was
+stopped and its temporary world deleted. No commit, push or publication was
+performed; generated structure placement remains a manual client check.
+
+## Cave Dungeon parity
+
+`1.0.1.92-beta.1` closes the Cave Dungeon terrain exclusion documented in .91.
+Root `AgeStructureSelection.error` permits Dungeons on noise terrain, which
+includes Cave. The 26.3 feature and placement implementation were already in
+place; the port's shared lake/dungeon Cave rejection blocked authoring and,
+through the availability check, random selection. Splitting that validation
+permits Cave Dungeons without allowing Cave lakes or Flat/Void Dungeons.
+
+The two targets' `worldgen/placed_feature/dungeons.json` files compare exactly:
+vanilla monster_room, count 8, in-square and full-height uniform placement
+using above-bottom/below-top anchors. No legacy Y=0 assumption is introduced.
+Vanilla's solid floor/ceiling and opening-count requirements still determine
+successful placement. The 32-page cap and per-occurrence deterministic seed
+remain unchanged. New random Cave Ages now consider Dungeons automatically;
+old frozen plans are not changed.
+
+The extended `create_dungeons` fixture checks Cave stacking/cap and the
+remaining lake/Flat/Void restrictions. The random-structure matrix now requires
+Cave Dungeon coverage. `dungeons_probe` accepts an optional 1–4 chunk-side
+bound for manual tests; it is not run automatically, avoiding a large sync
+chunk-generation scan. Actual dungeon placement is handed to the client check.
+
+The .92 build and disposable server checks passed: Cave and surface authored
+fixtures, 32-page stacking/overflow, retained lake and Flat/Void rejection,
+and random-structure coverage including a Nether Cave Dungeon selection.
+Dungeon counts survived unload/reload and full restart; frozen random plans
+survived reseed. Placement JSON matched the 1.21.1 file byte-for-byte. The
+server was stopped and its temporary world deleted. No commit, push or
+publication was performed. No dungeon chunk scan was run automatically.
+
+## Biome-specific Nether and End materials
+
+`1.0.1.93-beta.1` ports root `AgeDimensionService.withBiomeMaterialRules`.
+The backend was using `caves.materialRule()` unchanged, which selects
+`minecraft:overworld_caves` and can apply Overworld grass to Nether biomes.
+The new noise-settings wrapper sequences the five vanilla End biomes' registered
+End rule, then the five vanilla Nether biomes' registered Nether rule, then
+the original terrain rule. This fixes Cave Nether coverings and the equivalent
+End/Nether mismatch in authored Standard, Amplified and Island noise Ages.
+It uses the active rule registry rather than copying vanilla material tables.
+
+All non-material settings are preserved. Dry Cave's AIR default fluid, empty
+aquifer config and minimum-relative sea level remain intact. Native Nether
+surface rules can still place their own lava patches; this does not restore
+flooded Cave aquifers. Flat/Void layer materials and custom feature materials
+are not rewritten. Old saved Ages pick up the rule when reloaded, but only
+newly generated chunks change; no generated blocks are retroactively edited.
+No profile field or network protocol change is required.
+
+The creation fixture verifies unchanged geometry/router/default blocks and
+fluids, aquifers and sea level for four noise presets, and round-trips the
+composed material rule with registry-aware codecs. `material_probe` limits
+generation to one terrain-stage chunk and reports actual block counts.
+
+Build, registry-aware rule codec tests and disposable server terrain checks
+passed. All five Nether Cave fixtures generated their native material families
+without grass/dirt: Nylium, Soul Sand/Soil, Basalt/Blackstone or Netherrack.
+Standard The End and Island End Highlands generated End Stone; Lush Cave's
+original Overworld materials remained present. Reload retained the rules, and
+fresh chunks after full restart again used Nylium/End Stone. No full feature
+or entity chunk scans were run. The server was stopped and temporary world
+deleted. Nothing was committed, pushed or published.
+
+## Structure-aware biome completion
+
+`1.0.1.94-beta.1` adapts root `AgeBiomeSelection.completeStructureBiomes` for
+explicit non-Native biome controllers. It reads compatible biome IDs from
+the active registered structure sets and shares this lookup with random
+structure eligibility, avoiding two different compatibility definitions.
+Repeated structure pages produce one requirement; Dungeons are excluded.
+Single with no supplied biome chooses from the intersection of all structure
+requirements and terrain-eligible biomes. No intersection leaves ordinary
+seeded filling intact. An explicit Single biome is never rewritten.
+
+Multi-biome completion adds one seeded compatible biome for each unmet
+requirement where a terrain-eligible candidate exists, before ordinary minimum
+filling. Root's salts, requirement order and shuffled candidate selection are
+preserved. Existing biome order and duplicate weights remain, but a structure
+can intentionally extend a pool beyond the usual minimum. Native and the
+port's no-controller fallback remain unchanged. Impossible requirements do
+not become new writing rejections: authored structure overrides still apply.
+No saved format, network protocol or generated chunks are changed.
+
+The completed-biome fixture accepts an optional structure page and checks
+32 seeds for compatible Single/Cave Fortress choices, common Village/Stronghold
+requirements, explicit End Single precedence, Native behavior, multi-biome
+prefix preservation and avoiding unnecessary additions for already-compatible
+or repeated structure pages. Existing biome plan codec checks remain in place.
+
+The .94 build and disposable server checks passed. Village Single and Tiny
+fixtures included compatible Plains; Cave Fortress Single selected Crimson
+Forest. The 32-seed authoring assertions and the preexisting no-structure
+completion checks passed. Saved generator pools survived unload/reload,
+terrain reseed and full restart. The server was stopped and its temporary
+world deleted. No structure-placement chunk scan was needed. Client book
+authoring remains a manual check; no commit, push or publication occurred.
+
+## Omitted biome-controller completion
+
+`1.0.1.95-beta.1` ports the no-controller branch of root `AgeBiomeSelection`
+and the first `AgeTraits.select` draw. The rank table and seed stream are
+shared with `PortRandomAgeSelection` rather than duplicated. The production
+seeded biome compiler uses that default when there is no explicit controller;
+the registry-only diagnostic overload retains its exact older defaults.
+Explicit controllers are unchanged. Native rolls with authored biomes, or
+Single rolls with more than one biome page, fall back by authored count to
+Single/Tiled/Medium. Other multi-biome rolls retain their distribution and
+ordinary minimum-only filling, plus .94's structure requirements.
+
+Void's omitted controller remains Single for empty pools and count-based
+for supplied biome pages. Cave's omitted Native roll follows the port's
+existing page-free seeded Single workaround; a native multi-cave source is
+still not implemented. Explicit Native is not silently converted. No other
+terrain, weather, lighting, color or body seed stream changes. Saved plans
+remain frozen through restart and terrain reseed; old Ages are not rewritten.
+
+The completed-biome diagnostic accepts `auto` and checks 128 seeds for all
+nine distribution results, independence from unrelated weather pages,
+authored prefix preservation, one/two-biome fallbacks, Void behavior and
+structure-aware completion. Existing explicit-controller checks still run.
+
+The .95 build and disposable-server checks passed. The expanded 128-seed
+matrix covered all distributions, authored one/two-biome rules and Cave pools.
+Created automatic Standard, Cave, Void and Cave Fortress fixtures, plus the
+unchanged full-random command and explicit Single/Native Cave controls.
+Generator pools survived unload/reload, reseed and full restart. A second seed
+produced Small regions with three biomes, while explicit Native Cave retained
+its Lush Caves source. No chunk-generation scan was needed. The server was
+stopped and its temporary world deleted. Client authoring remains a manual
+check; nothing was committed, pushed or published.
+
+## Omitted terrain completion
+
+`1.0.1.96-beta.1` adapts root `AgeRuntimeProfiles.selectForWriting`. A partly
+authored book without terrain starts with the shared ranked terrain draw;
+if unsupported, compatible profiles in stable ID order are indexed using
+`floorMod(Long.hashCode(seed), count)`. Explicit terrain is never substituted.
+Unlike root's feature-only candidate test, the port additionally preflights
+registry-backed biome restrictions to avoid selecting an unloadable Cave
+combination for supplied surface biomes. This is a deliberate compatibility
+guard while the broader writing/instability recovery remains unported.
+
+Binder availability checks now consider whether any supported terrain can
+host an omitted-terrain book instead of assuming Standard. The server resolves
+the actual terrain and biome plan once, then passes the resolved internal page
+view to material/feature compilers. The inferred terrain is appended internally,
+not inserted before original pages or written back to the book. Original
+indices and ordered modifiers remain intact. Environment controllers use the
+selected terrain, while sky colors and celestials still compile from original
+pages. Page-free random books retain their original path and seed streams.
+The chosen terrain and generator plans use existing saved fields, so no
+network protocol change or retroactive terrain reroll is introduced.
+
+The fixture checks 64 seeds for terrain coverage, deterministic selection,
+original page prefixes, Cave-only Fortress support, implied-fluid constraints,
+surface-biome compatibility, explicit terrain precedence and Binder
+availability. Generator placement still uses the previously ported routines.
+
+The .96 build and disposable server checks passed. The 64-seed assertions
+covered all six terrains, deterministic fallback, page-prefix preservation,
+explicit Flat, surface-biome protection and Cave-only Fortress availability.
+Created Sky-only, Fortress-only, Water-only, Plains-only, explicit Flat and
+full-random fixtures. A Water page retained Water as its implied lake fluid;
+Fortress-only selected Cave with eligible biomes. Plans survived unload/reload,
+reseed and full restart. The server was stopped and its temporary world
+deleted. No chunk scan was needed; client Binder checks remain manual.
+Nothing was committed, pushed or published.
+
+## Native Cave regions
+
+`1.0.1.97-beta.1` ports root `AgeBiomeSelection`'s full Native Cave pool and
+`AgeDimensionService.createBiomeSource`'s Native-to-Tiny mapping. New Native
+Cave plans retain distribution NATIVE with a saved recognized Cave/Nether
+list, and the backend uses `PortScaledBiomeSource` at scale 0 (or Fixed for
+a one-biome pool). Explicit Native biome pages remain prohibited. Both authored
+and page-free/omitted-controller paths use the same eligibility query; the
+temporary Native-to-Single Cave conversions are removed.
+
+Native pool data is permitted only for Cave terrain at backend validation.
+Other Native terrain sources are unchanged. Empty older Native Cave records
+still load the old Lush source; old Single choices also remain frozen. New
+Native pools are saved through the existing biome-plan codec without a new
+network protocol, but earlier betas cannot decode populated Native pools, so
+downgrading those saves is not supported. The current pool is passed to random
+structure eligibility rather than incorrectly assuming Lush Caves.
+
+The fixture verifies registry-derived pool ordering, old empty Native codec
+defaults, the actual generator source, deterministic Tiny-region equivalence,
+horizontal region variation and sampled pool membership without loading
+chunks. The omitted-controller matrix now expects Native Cave to remain
+Native with its full pool. This does not implement modded surface rules.
+
+The .97 build and disposable-server checks passed: explicit and omitted
+Native Cave, the full-random Native Cave path (seed 114), Native + Fortresses,
+explicit Single and the legacy Lush-only control. The vanilla registry pool
+contained nine biomes, including Sulfur Caves and all five Nether biomes;
+the actual Native source passed Tiny-equivalence and sample-membership checks.
+Pools survived unload/reload, reseed and full restart. The server was stopped
+and its temporary world deleted. No chunk scan was needed. Client exploration
+remains a manual check; nothing was committed, pushed or published.
+
 ## Verification of this first slice
 
 The 1.21.1 `compileJava` and `build` tasks passed offline after the backend

ports/mc263/README.md

@@ -5,8 +5,12 @@ with the Minecraft 1.21.1 release. The 26.3 backend persists separate Ages and
 their seeds. Books, the Book Binder, and the Ink Mixer work, and the Binder can
 author Standard, Amplified, Island, Flat, Void, or Cave terrain with supported
 biome-distribution pages, selected material/vegetation/structure features, and
-independent Age weather and lighting. Celestial systems, instability, crystal
-portals, and much of the 1.21.1 gameplay remain unported. Use a test world and keep a backup; do not
+independent Age weather and lighting, multiple authored or seeded celestial
+bodies and eclipses, biome/material completion, and random features/structures.
+Instability, crystal portals, discovery/stations, writing recovery and optional
+integration parity remain unfinished. The latest published beta is
+[1.0.1.98-beta.1](RELEASE_NOTES_1.0.1.98-beta.1.md).
+Use a test world and keep a backup; do not
 substitute this JAR for the 1.21.1 mod or import 1.21.1 saves.
 
 The entries below record how the port was built, including earlier alpha-only
@@ -947,6 +951,468 @@ reload, reseed, restart and unchanged sampled lighting/time. Actual rendered
 size remains a manual check. The test server stopped and its world was deleted.
 No commit/push/publication is performed until explicitly requested.
 
+The local `1.0.1.79-beta.1` slice adds shared color groups before **Normal
+Time**, tinting both its sun and moon as in 1.21.1. Use Number + Red/Green/
+Blue/White/Black pages before that controller; Length/Phase/Angle/Size can
+appear between the colors and Normal Time without losing the pending group.
+Normal Time consumes the group, so it does not tint a later Sky or Ambient
+Light Color target. Trailing colors still target the sky. Mixing, seeded
+unnumbered amounts and completed-group clamping use the existing color rules.
+
+The tint changes native sun/moon RGB only, retaining sprite transparency,
+weather fading, moon phases and existing size/orbit/time settings. It does
+not recolor stars, sunrise glow or change gameplay illumination. Older saved
+color profiles keep untinted bodies; new profiles save and sync their tint.
+Catalog protocol is now 7: use matching client/server builds. Standalone
+Sun/Moon controllers and independent per-body colors remain pending.
+
+Test **Link Panel → Zero Length → Zenith Phase → Number 24 → Red → Normal
+Time**, optionally with No Weather and Normal Lighting, for a red sun. Use
+Nadir Phase to view the same tint on the moon. Mix several colors, add a
+separate color group before Sky, and confirm that the Overworld stays normal
+after travel. Check glow transparency and persistence after reopening the
+world. The op fixture `create_celestial_color <name> <seed>
+<rising|zenith|setting|nadir> <red|green|blue|white|black> <0..24>` provides
+independently colored sky/ambient plus a frozen body for diagnostics.
+Client rendering remains a manual check; nothing is committed or published
+without an explicit request.
+
+The local `1.0.1.80-beta.1` slice supports one standalone **Sun** or **Moon**
+controller in place of Normal Time. Both accept the existing Color, Length,
+Phase, Direction, Angle and Size modifiers (including Number overrides).
+Sun omits the paired moon; Moon omits the paired sun and sunrise glow.
+Size applies to the selected standalone body, while Normal Time still sizes
+only its sun. A missing Sky selects Overworld; explicit Sky remains decisive,
+and non-Overworld body rendering is still pending.
+
+Standalone bodies use the root-style linear orbit rather than the native
+paired cycle's eased orbit. Zenith puts either body overhead, Nadir puts it
+below the world, and Rising/Setting place it at the horizon. Zero Length
+freezes that position. Gameplay skylight combines altitude with precipitation
+and the root 0.18 moonlight multiplier (overhead sun = 15, overhead moon = 6,
+below-horizon body = 4 under clear weather). Bright/Dark rules remain separate.
+Native background, stars and moon-phase schedules remain for this slice;
+multiple independent bodies, eclipse handling, and full seeded celestial
+completion are not yet supported. Catalog protocol is now 8.
+
+Test **Link Panel → Zero Length → Zenith Phase → Large Celestial → Sun**,
+then replace Sun with Moon in a new book. Each should show only that body
+overhead. Try Number + Color and Size, a moving/reversed cycle, and Nadir;
+confirm the paired Normal Time and Overworld are unaffected after travel.
+Restart and revisit. The diagnostic `create_body <name> <seed> <sun|moon>
+<rising|zenith|setting|nadir>` creates a red, large, east-bearing frozen body.
+More than one celestial controller is still rejected, not silently discarded.
+Nothing is committed or published without an explicit request.
+
+The local `1.0.1.81-beta.1` slice accepts multiple celestial controllers.
+Each Sun/Moon consumes its own preceding Color, Length, Phase, Direction,
+Angle and Size group; modifiers reset after that controller. Normal Time
+contributes a sun/moon pair with opposite phases and its usual sun-only Size.
+The 1.21.1 limit of **ten suns and ten moons** applies, counting pairs toward
+both limits. Unsupported duplicate modifiers within one group and dangling
+modifiers are still rejected; the full recovery/instability grammar is pending.
+
+Multiple bodies retain independent saved orbits/colors and draw using the
+native body resources, with suns before moons. Each has its own linear orbit;
+the first controller supplies the shared day timeline and native background/
+star/moon-phase schedules. Skylight combines positive-altitude suns (capped at
+1), or sums weaker moonlight when no sun contributes, matching the root
+aggregation rule. Explicit non-Overworld backgrounds still hide bodies.
+Catalog protocol is now 9. Older single-body/paired profiles remain unchanged.
+
+**Eclipse effects are not in this slice:** sky darkening, disc occlusion and
+corona effects will be ported next. Visual overlap alone is not an eclipse.
+
+Test two groups in one book: **Zero Length → Zenith Phase → Large Celestial
+→ Number 24 → Red → Sun**, then **Zero Length → Rising Phase → Small Celestial
+→ Number 24 → Blue → Moon** (with Link Panel first). Each should retain its
+own size, color and position. Try a moving/reversed third body, a Normal Time
+pair alongside a standalone body, restart, and travel back to an ordinary
+Age/Overworld. `/rivencraft_port age create_celestials <name> <seed>` creates a
+diagnostic three-body Age. Rendering remains a manual client check. Nothing
+is committed or published without an explicit request.
+
+The local `1.0.1.82-beta.1` slice adds eclipse effects to saved multi-body
+profiles. Contact is based on the central quarter-size discs, not their
+halos. Opposite-kind overlap progressively dims a moon and whitens a sun's
+corona. A visible eclipsed sun darkens the sky by up to 65% and reduces its
+sunlight contribution by up to 85%, using the 1.21.1 formulas. Other suns can
+still supply light; same-kind overlaps do not produce eclipses. Below-horizon
+overlap does not darken the visible sky.
+
+Each body's native transparent glow is followed by an ordinary-alpha central
+disc, so an eclipsing moon obscures the sun instead of showing it through the
+glow. During an eclipse the moon core uses the solid full-moon sprite, matching
+root's occluding disc; native phases are retained outside eclipse contact.
+Weather fading remains. Meshes are cached, rebuilt after atlas changes and
+closed with the sky renderer. No new image assets are needed. Existing Ages
+with multiple bodies get these derived effects without rebinding their books.
+
+Test **Link Panel → Zero Length → Zenith Phase → Sun → Zero Length → Zenith
+Phase → Large Celestial → Moon** (No Weather and Normal Lighting recommended).
+This holds an eclipse overhead. Change the Moon to Half Length in a new book
+to watch it pass across the sun. Verify opaque center/transparent glow, sky
+and ground darkening, restart and travel back to an ordinary dimension.
+The op fixture `/rivencraft_port age create_eclipse <name> <seed>
+<aligned|partial|clear|below|moving>` creates controlled comparisons.
+The multi-body fixture is now named `create_celestials`, avoiding a collision
+with the existing terrain-generation `create_multi` command. Catalog schema
+remains protocol 9. Explicit non-Overworld body rendering and broader seeded
+completion are still pending. Nothing is committed or published without an
+explicit request.
+
+The local `1.0.1.83-beta.1` correction makes standalone and multi-body authored
+moons use the **full-moon sprite in both glow and opaque-center passes**, as
+the 1.21.1 custom renderer does. Native dark lunar-phase pixels could become
+black patches once the new ordinary-alpha center pass made them opaque.
+The native Normal Time pair keeps its calendar phases. Eclipse geometry,
+darkening and corona formulas are unchanged; genuinely eclipsed moons still
+turn dark and obscure their overlapping sun.
+
+Read-only inspection of the reported `celest` save found all four body colors
+intact (`-1`, untinted). Its first moon and second sun share period, direction,
+phase, origin and bearing, creating a permanent eclipse after eclipse support
+was added. This is separate from the phase-sprite rendering correction. No
+saved orbits/colors are rewritten, and existing Ages need not be recreated.
+Please revisit `celest`, compare a nonaligned authored moon, check an eclipse
+and resource reload, then return to Overworld/Normal Time to confirm native
+phases are unaffected. This rendering correction still needs a client check.
+Nothing is committed or published without an explicit request.
+
+The local `1.0.1.84-beta.1` slice renders authored **Normal Time, Sun, Moon
+and multiple bodies over all four Sky styles**, including explicit Nether,
+End and animated Static. Backgrounds draw first; the existing authored body
+pass follows with its colors, sizes, orbits, opaque centers and eclipse effects.
+Nether retains its fog backdrop, End retains its native sky texture, and
+Static keeps animating. These are presentation changes only: no Nether/End
+terrain, ceiling, coordinate-scale or dragon behavior is introduced.
+
+Eclipses shade End/Static background tint and the Nether-style fog backdrop;
+gameplay light still uses the saved body profile. Native Overworld rendering
+and no-celestial Ages are unchanged. No new assets, saved fields or catalog
+protocol changes are needed. Already-created Ages with explicit backgrounds
+and authored celestials gain the rendering on update without rebinding.
+
+Test the same frozen overhead Sun/Moon book with **Nether Sky**, **End Sky**
+and **Static Sky**, then test a moving body and eclipse in each. Check body
+colors/size, no duplicate bodies, unchanged background style, Static animation,
+F3+T, restart and travel to Overworld. The existing diagnostic
+`age create_eclipse <name> <seed> <mode> [overworld|nether|end|static]` now
+accepts an optional explicit Sky for comparisons. Client rendering remains a
+manual check. Nothing is committed or published without an explicit request.
+
+The local `1.0.1.85-beta.1` slice randomizes a **bare Sun or Moon page** when
+a new Age is created. Each such controller gets its own deterministic color,
+size, bearing, phase, direction and length. Defaults use the root random-Age
+palette (mixing 1–3 colors), size 0.75×–1.75×, bearing 0–359°, full-cycle phase,
+either direction, and length 0.2–2 days with Legacy's 1-in-7 stopped-cycle
+chance. Sun/Moon counts still come from your pages; nothing adds extra bodies.
+
+This applies only when that controller has **no written celestial modifiers**.
+If its group includes Color, Size, Angle, Phase, Direction or Length, the
+existing explicitly authored behavior is retained, including defaults for
+its other fields. Sky/ambient colors consumed by their own target and unrelated
+terrain/weather/lighting pages do not make a body authored or reshuffle its
+random settings. Normal Time is unchanged. Groups use Age seed plus controller
+ordinal; repeated bare pages get independent settings. Choices are saved,
+not rerolled on GUI opening, reload/restart or terrain reseeding.
+
+Test a **new** book with **Link Panel → Sun → Moon → Sun**, optionally adding
+No Weather and Normal Lighting for visibility. Expect varied colors/sizes/
+orbits; some bodies can be below the horizon or stopped. Test an explicitly
+modified body in the same book, then restart and revisit. Existing Ages keep
+their original saved settings and are not randomized retroactively. The op
+fixture `age create_random_celestials <name> <seed>` tests independent seeded
+defaults and bounds. Nothing is committed or published without explicit request.
+
+The local `1.0.1.86-beta.1` slice completes the celestial branch for **new
+books with no celestial controller pages**, including Link-Panel-only books.
+The Age seed chooses **0–3 suns and 0–3 moons**, following the root random
+count draws. Each body receives the independent saved settings introduced
+in .85. An explicit Sun, Moon or Normal Time suppresses this extra-body
+completion entirely; its written controllers remain authoritative.
+
+A valid zero-sun/zero-moon result draws neither body nor sunrise glow, rather
+than accidentally falling back to a vanilla pair. This does not force Dark
+Lighting: background/star schedules and independent lighting retain their
+normal behavior. Random background selection remains independent of body
+counts, and all supported Sky styles can render the chosen bodies. Default
+sky colors retain their current behavior; this slice completes bodies only.
+
+Choices persist through restart and terrain reseeding. Existing Ages are not
+rerolled. Catalog protocol is now **10**, requiring matching client/server
+builds. Test several new Link-Panel-only books, plus books that contain only
+terrain/weather/lighting/Sky pages. Expect varied counts, including sun-only,
+moon-only and empty skies; some bodies may be below the horizon. Compare an
+explicit one-Sun book and a Normal Time book, then restart and revisit.
+`age create_completed_sky <name> <seed> [overworld|nether|end|static]` provides
+clear-weather Flat fixtures and reports a sample zero-body seed. The existing
+`age create_random` now also uses the completed celestial plan. Nothing is
+committed or published without explicit request.
+
+The local `1.0.1.87-beta.1` slice gives **new Link-Panel-only random Ages**
+a saved random sky/fog tint, matching 1.21.1's seeded palette and rounded
+mix of 1–3 colors. This completes the sky-color draw already reserved by the
+random celestial count selection. Body settings/counts are unchanged.
+
+Books containing symbol pages keep their authored/default color rules; a
+black authored sky remains black. Ambient lighting is not randomized by this
+change. Existing Ages retain their saved colors. No new saved fields or
+catalog protocol change is needed. Create several new Link-Panel-only books,
+check sky/fog colors and restart persistence, then compare an explicitly
+colored Sky book and an uncolored terrain-only book. Nothing is committed or
+published without explicit request.
+
+The local `1.0.1.88-beta.1` slice seed-completes **explicit biome distribution
+pages with missing biome pages**. Single Biome alone selects one eligible
+biome. Tiled/Grid/region controllers alone choose at least two distinct
+biomes, using 1.21.1's seeded continuation rule and the available pool as the
+maximum. With one authored biome they fill just the missing second biome;
+with two distinct authored biomes they add nothing. Repeated biome pages keep
+their weight but do not satisfy the distinct-biome minimum by themselves.
+
+Cave completion draws only recognized Cave/Nether biomes. Void supplies The
+Void only when no biome is authored; a multi-biome Void book needs sufficient
+explicit biome pages rather than acquiring an unwanted Void biome. Native
+still rejects biome pages. No-controller biome behavior is unchanged, and
+the broader recovery/instability grammar is not part of this slice.
+
+Test a new Link Panel + Tiny Biome Regions book, Single Biome alone, and Tiny
+with one/two specific biome pages. Also try Cave + Tiny and restart/revisit.
+The operator fixture is `age create_completed_biomes <name> <seed> <terrain>
+<distribution>`; `age biome_pool <name>` inspects the generator without loading
+chunks. Existing Age pools do not change. Nothing is committed or published
+without explicit request.
+
+The local `1.0.1.89-beta.1` slice supports **unpaired Block/Fluid pages**.
+When no feature immediately follows a material, the Age seed and original
+page position choose a compatible implied feature, following 1.21.1's model.
+Explicit material → feature pairs remain unchanged. Consecutive material
+pages each receive their own selection; the resulting choices may repeat.
+Only the saved feature plans gain these implied choices, not extra physical
+pages in the book.
+
+Solid candidates are Rocks, Floating Islands, Tendrils, Spheres, Spikes and
+Obelisks, restricted by terrain. Cave permits Tendrils/Spheres; Void also
+permits Floating Islands. Flat excludes Rocks. Fluid candidates are the three
+lake types on supported surface noise terrain. An unpaired fluid on Flat,
+Void or Cave is still refused because no compatible lake implementation is
+available there. Explicit incompatible pairings and existing 32-feature
+limits are unchanged; the full recovery/instability grammar remains pending.
+
+Test Link Panel + Glowstone, consecutive Glowstone/Stone pages, and an unpaired
+Water page on Standard terrain. Compare an explicit Glowstone → Tendrils
+pair, try a solid on Cave/Void, and restart/revisit. Existing Ages retain
+their saved features. Operator diagnostics: `age create_implied_material
+<name> <seed> <terrain> <material-id>` and `age feature_plan <name>` (no chunk
+generation). Nothing is committed or published without explicit request.
+
+The local `1.0.1.90-beta.1` slice adds **random material features to new
+Link-Panel-only Ages**. The Age seed rolls 0–2 distinct feature types using
+1.21.1's Legacy rank weighting, then chooses a registered compatible solid
+or source fluid for each. Candidates are Rocks, Floating Islands, Tendrils,
+Spheres, Spikes, Obelisks and the three lake types, filtered by terrain.
+
+The same creation pass rolls rare Skylands (1-in-8 on noise terrain), Crystal
+Formations (1-in-10 on exposed surface terrain), and Star Fissures using the
+root small-feature grammar. These are additional to the 0–2 material features.
+Random structure selection and page-eligibility config remain future port
+work. Authored books do not gain unrequested random features, and existing
+Age plans are not rerolled. Choices persist through restart and reseed.
+
+Test several new Link-Panel-only books for varied material features, including
+Ages with none; compare an explicitly authored book and revisit after restart.
+For controlled checks, `age create_random_features <name> <seed> <terrain>`
+creates a feature-only fixture and `age feature_plan <name>` reports its
+saved generator choices without generating chunks. `age create_random` uses
+the same production selector. Nothing is committed or published without
+explicit request.
+
+The local `1.0.1.91-beta.1` slice ports **random structure selection** from
+1.21.1. New Link-Panel-only Ages roll 0–2 distinct structure families in
+addition to .90's material features. Legacy ranks prefer Villages, Strongholds
+and Mineshafts, followed by Dungeons/Fortresses; newer structures are rarer.
+The 26.3 Abandoned Camps page joins that rare pool. Candidates must support
+the terrain and at least one biome in the actual selected biome pool.
+
+A saved structure-control flag distinguishes an intentionally empty selection
+from older Ages' native behavior. Unselected page-controlled structure sets
+are disabled even when no structures were chosen; other native structure
+families remain governed by vanilla biome rules. Authored pages retain their
+biome override behavior, and old saved Ages are not changed. Cave Dungeons
+remain excluded by the port's existing terrain restriction; this is a known
+remaining difference from 1.21.1, not a new root behavior.
+
+Test several new random Ages, including a restart/revisit, and compare an
+authored Village book. For focused checks, `age create_random_structures
+<name> <seed> <terrain> <biome-id|native>` creates a controlled fixture;
+`age feature_plan <name>` reports the frozen selection, including Dungeons.
+No catalog protocol change is needed. Nothing is committed or published
+without explicit request.
+
+The local `1.0.1.92-beta.1` slice enables **Dungeons on Cave terrain**, including
+Nether cave biomes, matching 1.21.1's noise-terrain support. The already-ported
+placement JSON is byte-identical to root: eight vanilla monster-room attempts
+per page, uniformly from one block above the minimum to one below the maximum
+build height. Vanilla still requires a suitable enclosed chamber; an attempt
+is not a guaranteed dungeon. Stacking up to 32 pages is unchanged.
+
+Only the combined Cave dungeon/lake rejection was split: lakes remain rejected
+there, and Flat/Void still reject Dungeons. New random Cave Ages can now select
+Dungeons through .91's normal eligibility/rank rules. Existing saved plans
+are unchanged. `age create_dungeons <name> <seed> cave` creates an eight-page
+fixture. `age dungeons_probe <name> [chunks]` optionally limits the search to
+1–4 chunks per side; omitting it retains the previous 4×4 search. That probe
+generates chunks and is reserved for manual placement checks.
+
+Test Cave + Dungeons, optionally stacking pages for visibility; use spectator
+mode to find monster rooms and compare a Nether-biome Cave Age. This slice's
+server validation checks authoring and persistence without generating a large
+region. No saved-field/protocol change is needed. Nothing is committed or
+published without explicit request.
+
+The local `1.0.1.93-beta.1` slice fixes **Nether and End biome materials on
+noise terrain**, including Nether biomes in Cave Ages. The port had retained
+the vanilla terrain's Overworld material rules, which could coat Nether
+biomes in grass. It now ports 1.21.1's biome rule layer: the five vanilla End
+biomes use the registered End rule, the five vanilla Nether biomes use the
+registered Nether rule, and all other biomes retain the terrain's original
+rules. Nether coverings include Nylium, Soul Sand/Soil, Basalt and Blackstone
+where their native rules select them; End areas use End Stone.
+
+Noise geometry, biome selection, lighting, default fluids, sea level and dry
+Cave aquifer settings remain unchanged. This is not a Flat/Void layer rewrite.
+The correction applies after reload to **new chunks only** in existing Ages;
+already generated grass is not replaced. Test a new Nether-biome Cave Age
+and End-biome Standard/Island Age, or explore new chunks after restarting.
+
+Operator fixtures: `age create_biome_surface <name> <seed> <terrain> <biome-id>`
+and `age material_probe <name> [chunk_x chunk_z]`. The latter examines one
+terrain-stage chunk (default 0,0) without feature, lighting or entity generation. Nothing is committed
+or published without explicit request.
+
+The local `1.0.1.94-beta.1` slice ports **structure-aware completion of explicit
+biome distributions** from 1.21.1. Single Biome without a supplied biome now
+prefers a biome compatible with every authored structure page, when a common
+candidate exists. Cave + Single + Nether Fortresses therefore selects an
+eligible Cave/Nether biome rather than an unrelated cave biome. If there is
+no common candidate, ordinary seeded filling and authored structure overrides
+remain available, as in root.
+
+For multi-biome controllers, each uncovered structure requirement can add one
+compatible biome from the terrain's available pool. This is an intentional
+exception to ordinary minimum-only filling: an already-full pool may gain
+another biome for its structure pages. Supplied biomes, their order and
+duplicate weights remain intact. A supplied Single Biome is never replaced,
+Native remains unchanged, and Dungeons impose no biome requirement. The
+no-controller fallback remains unchanged in this slice.
+
+Test Single Biome + Villages without biome pages, Cave + Single Biome + Nether
+Fortresses, and a multi-biome book with structures. Compare an explicit End
+Single Biome + Villages to confirm that authored override still works.
+`age create_completed_biomes <name> <seed> <terrain> <distribution> [structure-page-id]`
+now accepts an optional structure fixture. Existing Ages are not rerolled;
+restart/reseed retains completed pools. Nothing is committed or published
+without explicit request.
+
+The local `1.0.1.95-beta.1` slice seed-completes **omitted biome controllers**
+in partly authored books, using 1.21.1's first AgeTraits distribution draw.
+Native, Single and Medium are common; the other supported distributions are
+rarer. Explicit controllers still win. Supplied biomes are never discarded:
+a Native roll with authored biomes falls back by count, as does a Single roll
+with multiple biome pages. Other seeded multi-biome controllers are retained,
+so a lone supplied biome may receive a second biome to meet the minimum.
+
+Void without biome pages still uses The Void; supplied Void biome pages keep
+their existing count-based behavior. An omitted controller that rolls Native
+on Cave terrain uses the same seeded Single fallback already used by random
+Ages, since the port has no native multi-cave source. Explicit Native Cave
+behavior remains unchanged. Structure-aware completion from .94 applies to
+the resulting nonnative controller. Full Link-Panel-only random generation
+retains its existing selector and seeds.
+
+Test new terrain-only books without biome controllers, one/two supplied biome
+pages without a controller, and Cave + Nether Fortresses without a biome
+controller. Compare an explicit Single Biome book and restart/revisit.
+`age create_completed_biomes <name> <seed> <terrain> auto [structure-page-id]`
+provides an omitted-controller fixture. Existing Ages are not rerolled.
+Nothing is committed or published without explicit request.
+
+The local `1.0.1.96-beta.1` slice seed-completes **omitted terrain pages** in
+partly authored books. It starts with the same ranked terrain draw as random
+Ages, following 1.21.1's `selectForWriting` model. If that terrain cannot host
+the supplied features/materials, a deterministic fallback chooses a compatible
+terrain in stable profile order. The port also preflights its current biome
+restrictions, avoiding an automatic Cave choice for supplied surface biomes.
+
+Explicit terrain still wins and incompatible explicit combinations remain
+rejected. Missing-terrain Fortress books can now bind using Cave terrain;
+unpaired fluids use supported surface noise terrain. No extra random features
+are added to partly authored books. The original book page list stays intact;
+the chosen terrain is appended only to internal generation input so material
+and color/controller indices do not shift. Sky/color/celestial compilation
+still reads the original pages. Fully random Link-Panel-only Ages retain their
+existing selector. Already-created Ages do not change terrain.
+
+Test several new books with Sky or a feature but no terrain page, Nether
+Fortresses alone, and an unpaired Water page. Compare an explicit Flat book
+and a Plains biome page without terrain; the latter must not choose Cave.
+`age create_auto_terrain <name> <seed> <page-id>` exercises the production
+selector for one-page fixtures. Restart and revisit to confirm persistence.
+Nothing is committed or published without explicit request.
+
+The local `1.0.1.97-beta.1` slice ports **Native Cave biome distribution** from
+1.21.1. A new Cave + Native book now freezes the full recognized Cave/Nether
+biome pool and distributes it with the existing seeded Tiny-region sampler,
+instead of forcing Lush Caves. An omitted controller or random Cave Age that
+rolls Native now uses that same pool rather than converting to Single.
+Random structures inspect the saved pool, so eligible Nether structures are
+no longer hidden behind an assumed Lush-only source.
+
+Existing Single Cave Ages remain Single. Old empty Native Cave records keep
+their Lush fallback; they are not silently expanded on load. Other Native
+terrains remain unchanged, and explicit Native still rejects biome pages.
+Pools persist across restart/reseed; reseeding can still change future region
+layout. Modded biome surface-rule integration remains separate pending work.
+Back up before updating and do not downgrade worlds containing new Native
+Cave pools to earlier beta builds.
+
+Test a **new** Cave + Native Biomes book without individual biome pages,
+explore multiple regions, then restart/revisit. Compare an explicit Single
+Cave book and an existing old Cave Age. The existing
+`age create_completed_biomes <name> <seed> cave native` fixture also checks
+the native source against Tiny's sampler without generating chunks.
+Nothing is committed or published without explicit request.
+
+### Accelerated random block ticks
+
+The local `1.0.1.98-beta.1` slice ports the **Accelerated** environment page
+from 1.21.1. Repeated pages stack: each adds three extra random positions per
+eligible block section per tick. Only already-loaded chunks within one chunk
+of players are candidates; no extra chunks are loaded. Defaults match 1.21.1:
+at most eight candidate chunks and 16,384 attempted positions per Age tick,
+shared across sections with rotating selection. These limits live in
+`config/rivencraft-local.toml` under `accelerated_age`; setting
+`max_random_tick_attempts_per_tick` to zero disables the extra ticks.
+
+This affects random-ticking blocks such as crops and saplings, not entities,
+machines, scheduled block ticks, or the day/night clock. The authored page
+count persists with the Age across unload/reload, reseeding and restart.
+Existing Ages default to zero; pageless random Ages do not gain Accelerated
+automatically. Instability costs remain part of the pending instability port.
+
+Test two otherwise comparable new Ages, one with a single Accelerated page
+and one with repeated pages. Plant crops/saplings with suitable light and
+space, remain nearby, and compare growth. Revisit after restart. The operator
+command `/rivencraft_port age acceleration <name>` reports the saved count
+and current budgets. Disposable-server fixture
+`age create_accelerated <name> <seed> <pages>` checks authoring and bounded
+attempt arithmetic and creates a Flat Age; it does not prove live growth.
+Build and disposable dedicated-server checks passed for counts 0, 1 and 32,
+overflow/disabled budget arithmetic, unload/reload, reseed and full restart.
+No player was connected for the server checks, so live growth remains an
+in-game acceptance check. The test server was stopped and its world removed.
+
 From the repository root:
 
 ```sh

ports/mc263/RELEASE_NOTES_1.0.1.93-beta.1.md

@@ -0,0 +1,83 @@
+# Rivencraft 26.3 beta 1.0.1.93-beta.1
+
+Collects the player-validated port slices .79–.93 since 1.0.1.78-beta.1.
+This beta is not yet feature-complete with Minecraft 1.21.1.
+
+## Celestial writing and rendering
+
+- Ported standalone Sun and Moon pages and multiple independently authored
+  bodies, up to ten of each. Each controller consumes its own ordered Color,
+  Length, Phase, Direction, Angle and Size modifiers; Number pages fine-tune
+  supported values. Normal Time retains its paired sun/moon behavior.
+- Color groups before Normal Time tint both bodies; independent Sun/Moon
+  groups can use different colors. Authored moons use full-moon sprites as in
+  1.21.1; native Normal Time retains calendar moon phases.
+- Authored bodies render over Overworld, Nether, End and animated Static
+  backgrounds. Opaque centers retain transparent glows. Eclipse alignment
+  affects body color, background shading and gameplay sky light.
+- Bare Sun/Moon pages receive independent seeded colors, sizes, bearings,
+  phases, directions and lengths, including stopped cycles. Explicit modifier
+  groups retain their authored behavior.
+- Books without celestial controllers seed-complete 0–3 suns and 0–3 moons.
+  Empty skies do not accidentally draw a vanilla pair. Explicit controllers
+  suppress extra-body completion. Link-Panel-only random Ages also receive
+  seeded sky/fog colors using the 1.21.1 palette.
+- All resolved settings are saved, not rerolled by viewing a book, restarting,
+  or reseeding future terrain. Existing Age profiles remain unchanged.
+
+## Biome and feature completion
+
+- Explicit biome-distribution pages can now seed-complete missing biome
+  pools. Single selects one; other nonnative controllers require two distinct
+  biomes. Fully omitted pools use the seeded continuation rule, bounded by the
+  available biome pool. Authored pools fill only the missing minimum.
+- Supplied biome order and duplicate weights are retained. Two distinct
+  supplied biomes do not acquire an unwanted third biome. Cave pools use
+  recognized Cave/Nether biomes; Void does not inject The Void alongside
+  supplied biome pages.
+- Unpaired Block/Fluid pages receive seeded terrain-compatible implied
+  features. Consecutive materials resolve independently; explicit pairs remain
+  authoritative. Unsupported pairings and the current feature caps remain.
+- Link-Panel-only Ages roll 0–2 distinct material feature types with Legacy
+  rank weighting and compatible registered solids/source fluids. Additional
+  rare rolls cover Skylands, Crystal Formations and Star Fissures.
+- Random Ages also roll 0–2 distinct structure families, filtered by terrain,
+  registry availability and the chosen biome pool. Newer structures, including
+  26.3 Abandoned Camps, are rare candidates. An intentionally empty selection
+  disables page-controlled structure sets rather than enabling all of them.
+- Cave terrain now supports authored and randomly selected Dungeons, matching
+  1.21.1. Dungeon placement retains eight monster-room attempts per page and
+  modern build-height anchors. Flat/Void Dungeons and Cave lakes remain
+  unsupported.
+
+## Nether and End material correction
+
+- Ported 1.21.1's biome-specific material-rule layer for noise terrain. Nether
+  biomes in Cave Ages now use their native Netherrack, Nylium, Soul Sand/Soil,
+  Basalt and Blackstone rules instead of Overworld grass. End biomes use End
+  Stone. Other biomes retain the original terrain rules.
+- Geometry, biome selection, dry Cave aquifers and other environment settings
+  are preserved. Flat/Void layers and authored feature materials are unchanged.
+- Existing Ages pick up the correction after reload, but only new chunks
+  change. Already generated grass is not replaced.
+
+## Compatibility and validation
+
+- Requires Minecraft **26.3**, NeoForge **26.3.0.99**, and **Java 25**. Dynamic
+  Dimensions and Bad Packets are not required. Minecraft 1.21.1 is unchanged.
+- Catalog protocol is **10**: use matching client/server builds.
+- Player in-game checks passed for all included slices. Builds and targeted
+  disposable-server checks covered writing, seeded completion, codecs/catalog
+  round trips, terrain materials, reload, reseed and restart. Temporary servers
+  and test worlds were removed. This is not a full automated GameTest run.
+- Full writing recovery, discovery/stations, instability, portals and optional
+  integration parity remain unfinished. Random-page eligibility config also
+  remains pending; valuable/hazardous random materials currently lack the
+  finished version's instability scoring. Creative availability does not imply
+  full page support. Number-controlled Static resolution (#109) and time-page
+  naming (#110) remain separate work.
+- Beta save compatibility is not guaranteed. Back up worlds and keep the two
+  Minecraft version tracks and saves separate.
+
+Report issues and help improve the wiki at
+[BlackSheep Git](https://git.paddedcell.org/dnorberg/rivencraft).

ports/mc263/RELEASE_NOTES_1.0.1.98-beta.1.md

@@ -0,0 +1,63 @@
+# Rivencraft 26.3 beta 1.0.1.98-beta.1
+
+Collects the player-validated port slices .94–.98 since 1.0.1.93-beta.1.
+This beta is not yet feature-complete with Minecraft 1.21.1.
+
+## Seeded terrain and biome completion
+
+- Books without a Terrain page now choose terrain using the 1.21.1 weighted
+  selector. Incompatible choices are replaced with a seeded compatible terrain;
+  explicit Terrain pages retain their authored behavior.
+- Omitted biome controllers now use the seeded weighted distribution selector.
+  Supplied biome pages are retained, with missing minimum slots completed.
+  Void without biome pages still uses The Void. Link-Panel-only random Ages
+  retain their existing selection path.
+- Missing nonnative biome pools account for authored structures. Single chooses
+  a terrain-compatible biome satisfying all structure requirements where one
+  exists. Multiple-biome distributions add compatible biomes for unmet structure
+  requirements before completing their ordinary minimum. Explicit Single
+  choices are never replaced.
+- New Native Cave Ages freeze the full recognized Cave/Nether biome pool and
+  distribute it using seeded Tiny regions, matching the 1.21.1 implementation.
+  This includes recognized modded cave biomes. Existing empty Native Cave
+  profiles retain their previous Lush Caves fallback; explicit Single is unchanged.
+- Removing Nether-style biomes from the default Native Cave pool is separate
+  planned work for both versions in issue #111, not part of this release.
+
+## Accelerated pages
+
+- Ported the Accelerated environment page. Repeated pages stack, each adding
+  three extra random positions per eligible block section per tick near players.
+- Defaults match 1.21.1: at most eight already-loaded candidate chunks and
+  16,384 extra random-tick attempts per Age tick, shared fairly across sections.
+  No extra chunks are force-loaded.
+- Limits are configurable in `config/rivencraft-local.toml`, under
+  `accelerated_age`. A zero attempt budget disables the extra ticks.
+- Page counts persist across unload/reload, reseeding and restart. Existing
+  Ages default to zero. Pageless random Ages do not gain Accelerated automatically.
+- This currently affects random-ticking blocks such as crops and saplings.
+  Machine/block-entity acceleration is deferred for both versions under issue
+  #112; entities and scheduled block ticks are also unaffected. Instability
+  scoring remains part of the unfinished instability port.
+- Operator command `/rivencraft_port age acceleration <name>` reports the
+  saved page count and current budgets.
+
+## Compatibility and validation
+
+- Requires Minecraft **26.3**, NeoForge **26.3.0.99**, and **Java 25**. Dynamic
+  Dimensions and Bad Packets are not required. Minecraft 1.21.1 is unchanged.
+- Catalog protocol remains **10**. Use matching client/server builds.
+- Player in-game checks passed. Builds and targeted disposable-server checks
+  covered seeded completion, Native Cave sampling, tick-budget arithmetic,
+  unload/reload, reseeding and restart. Test servers were stopped and their
+  worlds removed. This was not a full automated GameTest run.
+- Back up worlds before updating. New populated Native Cave profiles cannot
+  be read by earlier beta builds; do not downgrade those saves. Keep Minecraft
+  1.21.1 and 26.3 saves separate.
+- Full writing recovery, discovery/stations, instability, crystal portals and
+  optional integration parity remain unfinished. Random-page eligibility config
+  and modded biome surface-rule integration also remain pending. Creative page
+  availability does not imply full support.
+
+Report issues and help improve the wiki at
+[BlackSheep Git](https://git.paddedcell.org/dnorberg/rivencraft).

ports/mc263/gradle.properties

@@ -7,4 +7,4 @@ neo_version=26.3.0.99
 mod_id=rivencraft
 mod_name=Rivencraft
 mod_license=LGPL-3.0-or-later
-mod_version=1.0.1.78-beta.1
+mod_version=1.0.1.98-beta.1

ports/mc263/port_en_us.json

@@ -9,33 +9,35 @@
   "item.rivencraft.page.symbol.implemented": "Implemented in 26.3; book and terrain requirements still apply.",
   "symbol.rivencraft.weather.normal.description": "Use an independent normal weather cycle. Cave terrain keeps weather off.",
   "symbol.rivencraft.sky.overworld.description": "Use the native Overworld sky. Terrain and lighting remain independently authored.",
-  "symbol.rivencraft.sky.nether.description": "Use a Nether-style sky and reddish fog, without Nether terrain or gameplay rules.",
-  "symbol.rivencraft.sky.end.description": "Use the native End sky backdrop, without End terrain or a dragon fight.",
-  "symbol.rivencraft.sky.static.description": "Animated static surrounds the Age. Preceding color pages tint it; otherwise it is gray.",
+  "symbol.rivencraft.sky.nether.description": "Use a Nether-style reddish fog backdrop. Authored celestials render over it; terrain and gameplay rules remain independent.",
+  "symbol.rivencraft.sky.end.description": "Use the native End sky backdrop with authored celestials over it, without End terrain or a dragon fight.",
+  "symbol.rivencraft.sky.static.description": "Animated static surrounds the Age, behind authored celestials. Preceding colors tint it; otherwise it is gray.",
   "symbol.rivencraft.lighting.ambient_color": "Ambient Light Color",
   "symbol.rivencraft.lighting.ambient_color.description": "Apply preceding shared colors to ambient light. Use Bright separately for full effective ambient lighting.",
   "symbol.rivencraft.number.description": "Before Color: value × 10 per channel. Before Length: value × 0.08 days. Before Phase/Angle: value × 15 degrees. Before Size: 0.25× to 3× (0-24).",
-  "symbol.rivencraft.size.small.description": "Before Normal Time: render the sun at 0.5× size. Its paired moon stays normal-sized, matching 1.21.1. A preceding Number overrides the size.",
-  "symbol.rivencraft.size.normal.description": "Before Normal Time: render the sun at 1× size. A preceding Number selects 0.25× through 3× (0-24). Its paired moon is unchanged.",
-  "symbol.rivencraft.size.large.description": "Before Normal Time: render the sun at 2× size. A preceding Number selects 0.25× through 3× (0-24). Its paired moon is unchanged.",
-  "symbol.rivencraft.angle.north.description": "Before Normal Time: set the native celestial orbit bearing to 0 degrees. A preceding Number overrides Angle in 15-degree steps.",
-  "symbol.rivencraft.angle.east.description": "Before Normal Time: set the native celestial orbit bearing to 90 degrees. A preceding Number overrides Angle in 15-degree steps.",
-  "symbol.rivencraft.angle.south.description": "Before Normal Time: set the native celestial orbit bearing to 180 degrees. A preceding Number overrides Angle in 15-degree steps.",
-  "symbol.rivencraft.angle.west.description": "Before Normal Time: set the native celestial orbit bearing to 270 degrees. A preceding Number overrides Angle in 15-degree steps.",
-  "symbol.rivencraft.phase.rising.description": "Before Normal Time: start this Age's native cycle at sunrise. A preceding Number overrides Phase in 15-degree steps from midnight.",
-  "symbol.rivencraft.phase.zenith.description": "Before Normal Time: start this Age's native cycle at noon. With Zero Length it remains noon.",
-  "symbol.rivencraft.phase.setting.description": "Before Normal Time: start this Age's native cycle at sunset. A preceding Number overrides Phase in 15-degree steps from midnight.",
-  "symbol.rivencraft.phase.nadir.description": "Before Normal Time: start this Age's native cycle at midnight. With Zero Length it remains midnight.",
-  "symbol.rivencraft.direction.clockwise.description": "Before Normal Time: advance this Age's native day cycle in its usual direction.",
-  "symbol.rivencraft.direction.counterclockwise.description": "Before Normal Time: run this Age's native day cycle in reverse. Does not change the Overworld clock.",
-  "symbol.rivencraft.celestial.normal_time.description": "Use the native sun/moon cycle with Length, Phase, Direction, Angle, and sun Size modifiers. Without a Length, use one normal day.",
-  "symbol.rivencraft.period.zero.description": "Before Normal Time: freeze the Age's day timelines at the written Phase, or a saved seeded time if Phase is omitted. A preceding Number overrides the Length.",
-  "symbol.rivencraft.period.half.description": "Before Normal Time: a half-length day (twice as fast). A preceding Number sets Length to value × 0.08 days.",
-  "symbol.rivencraft.period.full.description": "Before Normal Time: a normal-length day. A preceding Number sets Length to value × 0.08 days.",
-  "symbol.rivencraft.period.double.description": "Before Normal Time: a double-length day (half as fast). A preceding Number sets Length to value × 0.08 days.",
-  "symbol.rivencraft.color.red.description": "Add red to the next sky or Ambient Light Color target; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
-  "symbol.rivencraft.color.green.description": "Add green to the next sky or Ambient Light Color target; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
-  "symbol.rivencraft.color.blue.description": "Add blue to the next sky or Ambient Light Color target; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
+  "symbol.rivencraft.size.small.description": "Before Sun/Moon: 0.5× body size. Before Normal Time: size the sun only. A preceding Number overrides the size.",
+  "symbol.rivencraft.size.normal.description": "Before Sun/Moon: 1× body size. Before Normal Time: size the sun only. A preceding Number selects 0.25× through 3× (0-24).",
+  "symbol.rivencraft.size.large.description": "Before Sun/Moon: 2× body size. Before Normal Time: size the sun only. A preceding Number selects 0.25× through 3× (0-24).",
+  "symbol.rivencraft.angle.north.description": "Before Normal Time, Sun or Moon: set orbit bearing to 0 degrees. A preceding Number overrides Angle in 15-degree steps.",
+  "symbol.rivencraft.angle.east.description": "Before Normal Time, Sun or Moon: set orbit bearing to 90 degrees. A preceding Number overrides Angle in 15-degree steps.",
+  "symbol.rivencraft.angle.south.description": "Before Normal Time, Sun or Moon: set orbit bearing to 180 degrees. A preceding Number overrides Angle in 15-degree steps.",
+  "symbol.rivencraft.angle.west.description": "Before Normal Time, Sun or Moon: set orbit bearing to 270 degrees. A preceding Number overrides Angle in 15-degree steps.",
+  "symbol.rivencraft.phase.rising.description": "Before a celestial controller: start the sun or standalone moon at rising. A preceding Number overrides Phase in 15-degree steps from Nadir.",
+  "symbol.rivencraft.phase.zenith.description": "Before a celestial controller: start the sun or standalone moon overhead. Zero Length holds this position.",
+  "symbol.rivencraft.phase.setting.description": "Before a celestial controller: start the sun or standalone moon at setting. A preceding Number overrides Phase in 15-degree steps from Nadir.",
+  "symbol.rivencraft.phase.nadir.description": "Before a celestial controller: start the sun or standalone moon below the world. Zero Length holds this position.",
+  "symbol.rivencraft.direction.clockwise.description": "Before Normal Time, Sun or Moon: advance this Age's celestial cycle in its usual direction.",
+  "symbol.rivencraft.direction.counterclockwise.description": "Before Normal Time, Sun or Moon: reverse this Age's celestial cycle. Does not change the Overworld clock.",
+  "symbol.rivencraft.celestial.normal_time.description": "Add a sun/moon pair. Preceding modifiers apply to this pair; Size affects its sun only. Colors tint both. Limit ten suns and ten moons per Age.",
+  "symbol.rivencraft.celestial.sun.description": "Add a sun. A bare page gets saved seeded color, size and orbit controls. Written modifiers preserve authored behavior and reset per controller. Moon alignment causes eclipses; limit ten suns.",
+  "symbol.rivencraft.celestial.moon.description": "Add a moon with weaker light. A bare page gets saved seeded color, size and orbit controls. Written modifiers preserve authored behavior and reset per controller. Sun alignment causes eclipses; limit ten moons.",
+  "symbol.rivencraft.period.zero.description": "Before Normal Time, Sun or Moon: freeze at the written Phase, or a saved seeded time if omitted. A preceding Number overrides the Length.",
+  "symbol.rivencraft.period.half.description": "Before Normal Time, Sun or Moon: a half-length cycle (twice as fast). A preceding Number sets Length to value × 0.08 days.",
+  "symbol.rivencraft.period.full.description": "Before Normal Time, Sun or Moon: a normal-length cycle. A preceding Number sets Length to value × 0.08 days.",
+  "symbol.rivencraft.period.double.description": "Before Normal Time, Sun or Moon: a double-length cycle (half as fast). A preceding Number sets Length to value × 0.08 days.",
+  "symbol.rivencraft.color.red.description": "Add red to the next Sky, Ambient Light Color or celestial controller; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
+  "symbol.rivencraft.color.green.description": "Add green to the next Sky, Ambient Light Color or celestial controller; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
+  "symbol.rivencraft.color.blue.description": "Add blue to the next Sky, Ambient Light Color or celestial controller; trailing colors tint the sky. Precede with a Number, or use a seeded amount.",
   "symbol.rivencraft.color.white.description": "Add equally to all RGB channels. Precede with a Number, or use a seeded amount.",
   "symbol.rivencraft.color.black.description": "Subtract equally from all RGB channels. Precede with a Number, or use a seeded amount.",
   "symbol.rivencraft.lighting.normal.description": "Use normal skylight and ambient brightness. Cave terrain remains without skylight.",
@@ -82,9 +84,12 @@
   "symbol.rivencraft.feature.red_shrubs.description": "Add red shrub patches to surface terrain with suitable ground.",
   "symbol.rivencraft.feature.abandoned_camps": "Abandoned Camps",
   "symbol.rivencraft.feature.abandoned_camps.description": "Allow abandoned camps on surface noise terrain, including outside their usual biomes.",
-  "symbol.rivencraft.block.generated.description": "Place immediately before a compatible feature; unpaired materials are not yet supported.",
-  "symbol.rivencraft.biome.native.description": "Use the terrain's native biome source; do not include Biome pages.",
+  "symbol.rivencraft.block.generated.description": "Modify the next compatible feature. Without a following feature, choose a compatible feature from the Age seed.",
+  "symbol.rivencraft.biome.native.description": "Use the terrain's default biome source. Cave uses Tiny regions from recognized Cave/Nether biomes. Do not include Biome pages.",
+  "symbol.rivencraft.feature.dungeons.description": "Add monster-room dungeon attempts throughout surface noise or Cave terrain, including Nether cave biomes. Not Flat or Void.",
+  "symbol.rivencraft.biome.single.description": "Use one biome across the Age. If omitted, choose an eligible biome from the Age seed.",
   "symbol.rivencraft.terrain.flat.description": "A level, biome-decorated landscape with its foundation at Y=0.",
+  "symbol.rivencraft.environment.accelerated.description": "Adds extra random block ticks near players in this Age. Repeated pages stack within server tick budgets; does not speed up entities or machines.",
   "symbol.rivencraft.feature.floating_islands.description": "Add high floating islands alongside noise, Flat, or Void terrain; not Cave terrain.",
   "symbol.rivencraft.feature.caves.description": "Add extra cave carving to noise terrain, including Cave; not Flat or Void.",
   "symbol.rivencraft.feature.ravines.description": "Add canyon carving to noise terrain; not Flat or Void. Skips Nether biomes.",

ports/mc263/src/main/java/net/dnorberg/rivencraft/PortConfig.java

@@ -0,0 +1,23 @@
+package net.dnorberg.rivencraft;
+
+import net.neoforged.neoforge.common.ModConfigSpec;
+
+/** Server-side limits shared with the 1.21.1 Accelerated implementation. */
+public final class PortConfig {
+    public static final ModConfigSpec SPEC;
+    public static final ModConfigSpec.IntValue ACCELERATED_MAX_CHUNKS;
+    public static final ModConfigSpec.IntValue ACCELERATED_MAX_ATTEMPTS;
+
+    static {
+        var builder = new ModConfigSpec.Builder();
+        builder.push("accelerated_age");
+        ACCELERATED_MAX_CHUNKS = builder.comment("Maximum already-loaded player-nearby chunks given extra random ticks per Age tick.")
+                .defineInRange("max_loaded_chunks", 8, 1, 64);
+        ACCELERATED_MAX_ATTEMPTS = builder.comment("Maximum extra random-tick positions sampled per Age tick, shared fairly across loaded sections; zero disables Accelerated.")
+                .defineInRange("max_random_tick_attempts_per_tick", 16384, 0, 65536);
+        builder.pop();
+        SPEC = builder.build();
+    }
+
+    private PortConfig() {}
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/Rivencraft.java

@@ -166,7 +166,8 @@ public final class Rivencraft {
     public static final Supplier<RecipeSerializer<LinkingBookRecipe>> LINKING_BOOK_RECIPE =
             RECIPE_SERIALIZERS.register("linking_book", () -> LinkingBookRecipe.SERIALIZER);
 
-    public Rivencraft(IEventBus modEventBus) {
+    public Rivencraft(IEventBus modEventBus, net.neoforged.fml.ModContainer container) {
+        container.registerConfig(net.neoforged.fml.config.ModConfig.Type.LOCAL, PortConfig.SPEC);
         BLOCKS.register(modEventBus);
         SOUNDS.register(modEventBus);
         ITEMS.register(modEventBus);
@@ -179,6 +180,7 @@ public final class Rivencraft {
         PortChunkGenerators.register(modEventBus);
         NeoForge.EVENT_BUS.addListener(RuntimeAgeBackend::onLevelLoad);
         NeoForge.EVENT_BUS.addListener(net.dnorberg.rivencraft.age.PortAgeWeather::onLevelTickPre);
+        NeoForge.EVENT_BUS.addListener(net.dnorberg.rivencraft.age.PortAcceleratedTicks::onLevelTickPost);
         NeoForge.EVENT_BUS.addListener(PortAgeCommands::register);
         NeoForge.EVENT_BUS.addListener(AgeCatalogSync::onLogin);
         NeoForge.EVENT_BUS.addListener(AgeCatalogSync::onLogout);

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/AgeCatalogSync.java

@@ -21,7 +21,7 @@ public final class AgeCatalogSync {
     }
 
     public static void registerPayloads(RegisterPayloadHandlersEvent event) {
-        var registrar = event.registrar("6");
+        var registrar = event.registrar("10");
         registrar.playToClient(AgeCatalogPayload.TYPE, AgeCatalogPayload.STREAM_CODEC);
         registrar.playToServer(AgeCatalogAckPayload.TYPE, AgeCatalogAckPayload.STREAM_CODEC,
                 (payload, context) -> {

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortAcceleratedTicks.java

@@ -0,0 +1,119 @@
+package net.dnorberg.rivencraft.age;
+
+import java.util.ArrayList;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+import net.dnorberg.rivencraft.PortConfig;
+import net.minecraft.resources.Identifier;
+import net.neoforged.neoforge.event.tick.LevelTickEvent;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.SectionPos;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.ChunkPos;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.level.chunk.LevelChunk;
+import net.minecraft.world.level.chunk.LevelChunkSection;
+import net.minecraft.util.RandomSource;
+
+/** Extra random block ticks from authored Accelerated pages, bounded to loaded player chunks. */
+public final class PortAcceleratedTicks {
+    public static final Identifier PAGE = Identifier.fromNamespaceAndPath("rivencraft", "environment/accelerated");
+
+    private PortAcceleratedTicks() {}
+
+    public static int pageCount(List<Identifier> pages) {
+        return (int) pages.stream().filter(PAGE::equals).count();
+    }
+
+    public static void configure(ServerLevel level, int pages) {
+        if (!(level instanceof PortAgeLevel)) throw new IllegalArgumentException("Not a Rivencraft Age");
+        level.getDataStorage().computeIfAbsent(PortAccelerationSettings.TYPE).setPages(pages);
+        level.getDataStorage().saveAndJoin();
+    }
+
+    public static int pages(ServerLevel level) {
+        return level.getDataStorage().computeIfAbsent(PortAccelerationSettings.TYPE).pages();
+    }
+
+    public static void onLevelTickPost(LevelTickEvent.Post event) {
+        if (event.getLevel() instanceof PortAgeLevel level) tick(level);
+    }
+
+    static void tick(ServerLevel level) {
+        int maximumAttempts = PortConfig.ACCELERATED_MAX_ATTEMPTS.get();
+        if (maximumAttempts == 0) return;
+        int pages = pages(level);
+        if (pages == 0) return;
+
+        List<ChunkPos> chunks = loadedPlayerChunks(level);
+        if (chunks.isEmpty()) return;
+        int maximumChunks = Math.min(chunks.size(), PortConfig.ACCELERATED_MAX_CHUNKS.get());
+        int first = Math.floorMod(level.getServer().getTickCount(), chunks.size());
+        List<TickSection> eligible = new ArrayList<>();
+        for (int offset = 0; offset < maximumChunks; offset++) {
+            ChunkPos pos = chunks.get((first + offset) % chunks.size());
+            LevelChunk chunk = level.getChunkSource().getChunkNow(pos.x(), pos.z());
+            if (chunk == null) continue;
+            LevelChunkSection[] sections = chunk.getSections();
+            for (int sectionIndex = 0; sectionIndex < sections.length; sectionIndex++) {
+                LevelChunkSection section = sections[sectionIndex];
+                if (!section.isRandomlyTickingBlocks()) continue;
+                int baseY = SectionPos.sectionToBlockCoord(chunk.getSectionYFromSectionIndex(sectionIndex));
+                eligible.add(new TickSection(pos, baseY, section));
+            }
+        }
+        if (eligible.isEmpty()) return;
+
+        // Legacy attempts three positions per random-ticking section per page. Divide
+        // the bounded total between sections before ticking any one of them, so a
+        // lower section cannot exhaust the entire budget ahead of surface crops.
+        int total = attemptBudget(pages, eligible.size(), maximumAttempts);
+        int perSection = total / eligible.size();
+        int remainder = total % eligible.size();
+        int firstSection = Math.floorMod(level.getServer().getTickCount(), eligible.size());
+        RandomSource random = level.getRandom();
+        for (int offset = 0; offset < eligible.size(); offset++) {
+            TickSection candidate = eligible.get((firstSection + offset) % eligible.size());
+            int samples = perSection + (offset < remainder ? 1 : 0);
+            for (int sample = 0; sample < samples; sample++) {
+                int x = random.nextInt(16);
+                int y = random.nextInt(16);
+                int z = random.nextInt(16);
+                BlockState state = candidate.section().getBlockState(x, y, z);
+                if (state.isRandomlyTicking()) {
+                    state.randomTick(level, new BlockPos(candidate.chunk().getMinBlockX() + x,
+                            candidate.baseY() + y, candidate.chunk().getMinBlockZ() + z), random);
+                }
+            }
+        }
+    }
+
+    static int attemptBudget(int pages, int sections, int maximumAttempts) {
+        if (pages < 0 || sections < 0 || maximumAttempts < 0)
+            throw new IllegalArgumentException("Negative accelerated tick budget input");
+        if (sections == 0) return 0;
+        long perSection = 3L * pages;
+        return perSection > maximumAttempts / (long) sections
+                ? maximumAttempts : (int) (perSection * sections);
+    }
+
+    private static List<ChunkPos> loadedPlayerChunks(ServerLevel level) {
+        Set<ChunkPos> chunks = new LinkedHashSet<>();
+        for (var player : level.players()) {
+            ChunkPos center = player.chunkPosition();
+            for (int x = -1; x <= 1; x++) {
+                for (int z = -1; z <= 1; z++) {
+                    int chunkX = center.x() + x;
+                    int chunkZ = center.z() + z;
+                    if (level.getChunkSource().hasChunk(chunkX, chunkZ)) {
+                        chunks.add(new ChunkPos(chunkX, chunkZ));
+                    }
+                }
+            }
+        }
+        return new ArrayList<>(chunks);
+    }
+
+    private record TickSection(ChunkPos chunk, int baseY, LevelChunkSection section) {}
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortAccelerationSettings.java

@@ -0,0 +1,24 @@
+package net.dnorberg.rivencraft.age;
+
+import com.mojang.serialization.Codec;
+import net.minecraft.resources.Identifier;
+import net.minecraft.world.level.saveddata.SavedData;
+import net.minecraft.world.level.saveddata.SavedDataType;
+
+/** Age-local authored page count, retained across unload, restart and reseeding. */
+final class PortAccelerationSettings extends SavedData {
+    private static final Codec<PortAccelerationSettings> CODEC = Codec.intRange(0, Integer.MAX_VALUE)
+            .fieldOf("pages").codec().xmap(PortAccelerationSettings::new, settings -> settings.pages);
+    static final SavedDataType<PortAccelerationSettings> TYPE = new SavedDataType<>(
+            Identifier.fromNamespaceAndPath("rivencraft", "acceleration"),
+            () -> new PortAccelerationSettings(0), CODEC);
+    private int pages;
+
+    private PortAccelerationSettings(int pages) { this.pages = pages; }
+    int pages() { return pages; }
+    void setPages(int pages) {
+        if (pages < 0) throw new IllegalArgumentException("Negative Accelerated page count");
+        this.pages = pages;
+        setDirty();
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortAgeColors.java

@@ -14,22 +14,27 @@ import org.joml.Vector3f;
 import org.joml.Vector3fc;
 
 /** Frozen shared-color writing, adapted from 1.21.1 AgeSkyProfile. -1 means native. */
-public record PortAgeColors(int sky, int ambient) {
+public record PortAgeColors(int sky, int ambient, int celestial) {
     public static final PortAgeColors NATIVE = new PortAgeColors(-1, -1);
     public static final Codec<PortAgeColors> CODEC = RecordCodecBuilder.create(instance -> instance.group(
             Codec.intRange(-1, 0xffffff).fieldOf("sky").forGetter(PortAgeColors::sky),
-            Codec.intRange(-1, 0xffffff).fieldOf("ambient").forGetter(PortAgeColors::ambient)
+            Codec.intRange(-1, 0xffffff).fieldOf("ambient").forGetter(PortAgeColors::ambient),
+            Codec.intRange(-1, 0xffffff).optionalFieldOf("celestial", -1).forGetter(PortAgeColors::celestial)
     ).apply(instance, PortAgeColors::new));
     public static final StreamCodec<RegistryFriendlyByteBuf, PortAgeColors> STREAM_CODEC = StreamCodec.composite(
-            ByteBufCodecs.INT, PortAgeColors::sky, ByteBufCodecs.INT, PortAgeColors::ambient, PortAgeColors::new);
+            ByteBufCodecs.INT, PortAgeColors::sky, ByteBufCodecs.INT, PortAgeColors::ambient,
+            ByteBufCodecs.INT, PortAgeColors::celestial, PortAgeColors::new);
     public static final Identifier AMBIENT = Identifier.fromNamespaceAndPath("rivencraft", "lighting/ambient_color");
     private static volatile Map<Identifier, PortAgeColors> clientColors = Map.of();
 
     public PortAgeColors {
-        if (sky < -1 || sky > 0xffffff || ambient < -1 || ambient > 0xffffff)
+        if (sky < -1 || sky > 0xffffff || ambient < -1 || ambient > 0xffffff
+                || celestial < -1 || celestial > 0xffffff)
             throw new IllegalArgumentException("Invalid Age color");
     }
 
+    public PortAgeColors(int sky, int ambient) { this(sky, ambient, -1); }
+
     public static void updateClient(Map<Identifier, PortAgeColors> colors) { clientColors = Map.copyOf(colors); }
 
     public static PortAgeColors forLevel(Level level) {
@@ -65,7 +70,7 @@ public record PortAgeColors(int sky, int ambient) {
 
     public static PortAgeColors compile(List<Identifier> pages, long seed) {
         if (!validNumbers(pages)) throw new IllegalArgumentException("Number pages must precede a supported Color, Length, Phase, Angle, or Size modifier");
-        int red = 0, green = 0, blue = 0, sky = -1, ambient = -1;
+        int red = 0, green = 0, blue = 0, sky = -1, ambient = -1, celestial = -1;
         boolean written = false;
         for (int i = 0; i < pages.size(); i++) {
             Identifier page = pages.get(i);
@@ -81,17 +86,43 @@ public record PortAgeColors(int sky, int ambient) {
                     case "color/white" -> { red += amount; green += amount; blue += amount; }
                     case "color/black" -> { red -= amount; green -= amount; blue -= amount; }
                 }
-            } else if (PortSkyStyle.forPage(page) != null || page.equals(AMBIENT)) {
+            } else if (PortSkyStyle.forPage(page) != null || page.equals(AMBIENT)
+                    || PortDayCycle.isController(page)) {
+                if (PortDayCycle.isController(page)) celestial = -1;
                 if (written) {
                     int rgb = clamp(red) << 16 | clamp(green) << 8 | clamp(blue);
-                    if (page.equals(AMBIENT)) ambient = rgb; else sky = rgb;
+                    if (page.equals(AMBIENT)) ambient = rgb;
+                    else if (PortDayCycle.isController(page)) celestial = rgb;
+                    else sky = rgb;
                 }
                 red = green = blue = 0;
                 written = false;
             }
         }
         if (written) sky = clamp(red) << 16 | clamp(green) << 8 | clamp(blue);
-        return new PortAgeColors(sky, ambient);
+        return new PortAgeColors(sky, ambient, celestial);
+    }
+
+    /** Only pageless random Ages receive a random sky tint, as in 1.21.1. */
+    public static PortAgeColors resolve(List<Identifier> pages, long seed) {
+        if (!pages.isEmpty()) return compile(pages, seed);
+        var random = new Random(seed ^ 0x534B5950524F464CL);
+        random.nextInt(5); // Root sky-style draw precedes the sky-color draw.
+        return new PortAgeColors(randomColor(random, true), -1);
+    }
+
+    /** Shared palette; retain .85's truncation for already-defined body defaults. */
+    static int randomColor(Random random, boolean rounded) {
+        int[] palette = {0xB74A50, 0xD9834B, 0xDBC574, 0x5AAB80, 0x6FA8DF, 0x9870B9, 0xD5DBE1, 0x252531};
+        int count = 1 + random.nextInt(3), red = 0, green = 0, blue = 0;
+        for (int i = 0; i < count; i++) {
+            int color = palette[random.nextInt(palette.length)];
+            red += color >> 16 & 255;
+            green += color >> 8 & 255;
+            blue += color & 255;
+        }
+        int offset = rounded ? count / 2 : 0;
+        return (red + offset) / count << 16 | (green + offset) / count << 8 | (blue + offset) / count;
     }
 
     private static int clamp(int value) { return Math.max(0, Math.min(255, value)); }

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortBiomeMaterialRules.java

@@ -0,0 +1,31 @@
+package net.dnorberg.rivencraft.age;
+
+import net.minecraft.core.Holder;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.data.worldgen.material.EndMaterialRules;
+import net.minecraft.data.worldgen.material.NetherMaterialRules;
+import net.minecraft.world.level.biome.Biomes;
+import net.minecraft.world.level.levelgen.NoiseGeneratorSettings;
+import net.minecraft.world.level.levelgen.material.MaterialRules;
+
+/** Root AgeDimensionService.withBiomeMaterialRules adapted to 26.3's rule registry. */
+final class PortBiomeMaterialRules {
+    private PortBiomeMaterialRules() {}
+
+    static Holder<NoiseGeneratorSettings> apply(HolderLookup.Provider registries, NoiseGeneratorSettings base) {
+        var biomes = registries.lookupOrThrow(Registries.BIOME);
+        var rules = registries.lookupOrThrow(Registries.MATERIAL_RULE);
+        var materials = MaterialRules.sequence(
+                MaterialRules.ifTrue(MaterialRules.isBiome(biomes, Biomes.THE_END, Biomes.END_HIGHLANDS,
+                        Biomes.END_MIDLANDS, Biomes.SMALL_END_ISLANDS, Biomes.END_BARRENS),
+                        MaterialRules.getRule(rules, EndMaterialRules.END)),
+                MaterialRules.ifTrue(MaterialRules.isBiome(biomes, Biomes.NETHER_WASTES, Biomes.SOUL_SAND_VALLEY,
+                        Biomes.CRIMSON_FOREST, Biomes.WARPED_FOREST, Biomes.BASALT_DELTAS),
+                        MaterialRules.getRule(rules, NetherMaterialRules.NETHER)),
+                base.materialRule().value());
+        return Holder.direct(new NoiseGeneratorSettings(base.noiseSettings(), base.defaultBlock(), base.defaultFluid(),
+                base.noiseRouter(), Holder.direct(materials), base.spawnTarget(), base.seaLevel(), base.disableMobGeneration(),
+                base.aquifers(), base.useLegacyRandomSource(), base.debugFunctions()));
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortBiomePlan.java

@@ -5,7 +5,7 @@ import com.mojang.serialization.codecs.RecordCodecBuilder;
 import java.util.List;
 import net.minecraft.resources.Identifier;
 
-/** Frozen authored biome choice; repeated entries retain their selection weight. */
+/** Frozen biome choice; Native may carry an explicit Cave pool. Repeats retain weight. */
 public record PortBiomePlan(Distribution distribution, List<Identifier> biomes) {
     public enum Distribution { NATIVE, SINGLE, TILED, GRID, TINY, SMALL, MEDIUM, LARGE, HUGE }
 
@@ -17,8 +17,7 @@ public record PortBiomePlan(Distribution distribution, List<Identifier> biomes)
 
     public PortBiomePlan {
         biomes = List.copyOf(biomes);
-        if (distribution == Distribution.NATIVE && !biomes.isEmpty()
-                || distribution == Distribution.SINGLE && biomes.size() != 1
+        if (distribution == null || distribution == Distribution.SINGLE && biomes.size() != 1
                 || distribution != Distribution.NATIVE && distribution != Distribution.SINGLE && biomes.size() < 2)
             throw new IllegalArgumentException("Invalid authored biome distribution");
     }

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortCelestialBody.java

@@ -0,0 +1,96 @@
+package net.dnorberg.rivencraft.age;
+
+import com.mojang.serialization.Codec;
+import com.mojang.serialization.codecs.RecordCodecBuilder;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.codec.ByteBufCodecs;
+import net.minecraft.network.codec.StreamCodec;
+
+/** One frozen authored orbit, using the same angular motion as 1.21.1 Body. */
+public record PortCelestialBody(int kind, double period, int stoppedTime, long originTick,
+                                int phaseTick, boolean clockwise, int bearing, float size, int color) {
+    public static final Codec<PortCelestialBody> CODEC = RecordCodecBuilder.create(instance -> instance.group(
+            Codec.intRange(1, 2).fieldOf("kind").forGetter(PortCelestialBody::kind),
+            Codec.doubleRange(0, 2).fieldOf("period").forGetter(PortCelestialBody::period),
+            Codec.intRange(0, 23999).fieldOf("stopped_time").forGetter(PortCelestialBody::stoppedTime),
+            Codec.LONG.fieldOf("origin_tick").forGetter(PortCelestialBody::originTick),
+            Codec.intRange(0, 23999).fieldOf("phase_tick").forGetter(PortCelestialBody::phaseTick),
+            Codec.BOOL.fieldOf("clockwise").forGetter(PortCelestialBody::clockwise),
+            Codec.intRange(-1, 359).fieldOf("bearing").forGetter(PortCelestialBody::bearing),
+            Codec.floatRange(0.25F, 3F).fieldOf("size").forGetter(PortCelestialBody::size),
+            Codec.intRange(-1, 0xffffff).fieldOf("color").forGetter(PortCelestialBody::color)
+    ).apply(instance, PortCelestialBody::new));
+    public static final StreamCodec<RegistryFriendlyByteBuf, PortCelestialBody> STREAM_CODEC = StreamCodec.composite(
+            ByteBufCodecs.VAR_INT, PortCelestialBody::kind, ByteBufCodecs.DOUBLE, PortCelestialBody::period,
+            ByteBufCodecs.VAR_INT, PortCelestialBody::stoppedTime, ByteBufCodecs.VAR_LONG, PortCelestialBody::originTick,
+            ByteBufCodecs.VAR_INT, PortCelestialBody::phaseTick, ByteBufCodecs.BOOL, PortCelestialBody::clockwise,
+            ByteBufCodecs.INT, PortCelestialBody::bearing, ByteBufCodecs.FLOAT, PortCelestialBody::size,
+            ByteBufCodecs.INT, PortCelestialBody::color, PortCelestialBody::new);
+
+    public PortCelestialBody {
+        if (kind != PortDayCycle.SUN && kind != PortDayCycle.MOON || !Double.isFinite(period)
+                || period < 0 || period > 2 || stoppedTime < 0 || stoppedTime >= 24000
+                || phaseTick < 0 || phaseTick >= 24000 || bearing < -1 || bearing > 359
+                || !Float.isFinite(size) || size < 0.25F || size > 3 || color < -1 || color > 0xffffff)
+            throw new IllegalArgumentException("Invalid celestial body");
+    }
+
+    public static PortCelestialBody of(PortDayCycle cycle, int kind, int color, boolean pairedMoon) {
+        int offset = pairedMoon ? 12000 : 0;
+        return new PortCelestialBody(kind, cycle.period(), (cycle.stoppedTime() + offset) % 24000,
+                cycle.originTick(), (cycle.phaseTick() + offset) % 24000, cycle.clockwise(),
+                cycle.bearing(), pairedMoon ? 1F : cycle.sunSize(), color);
+    }
+
+    public float angle(double nativeTicks) {
+        double time = period == 0 ? stoppedTime
+                : (clockwise ? 1 : -1) * (nativeTicks - originTick) / period + phaseTick;
+        return (float) (((time - 6000D) % 24000D) * (360D / 24000D));
+    }
+
+    public float light(long nativeTicks) {
+        return Math.max(0F, (float) Math.cos(Math.toRadians(angle(nativeTicks))))
+                * (kind == PortDayCycle.MOON ? 0.18F : 1F);
+    }
+
+    public net.minecraft.world.phys.Vec3 direction(double ticks) {
+        double orbit = Math.toRadians(angle(ticks)), axis = Math.toRadians(bearing < 0 ? -90 : bearing);
+        double lateral = Math.sin(orbit);
+        return new net.minecraft.world.phys.Vec3(Math.sin(axis) * lateral, Math.cos(orbit), Math.cos(axis) * lateral);
+    }
+
+    /** Root AgeSkyProfile.eclipseFor: contact uses the central quarter-size disc, not its halo. */
+    public float eclipse(java.util.List<PortCelestialBody> bodies, double ticks) {
+        float strongest = 0;
+        var direction = direction(ticks);
+        double radius = Math.atan((kind == PortDayCycle.SUN ? 30D : 20D) * size * 0.25D / 100D);
+        for (var other : bodies) {
+            if (other.kind == kind) continue;
+            double separation = Math.acos(Math.max(-1D, Math.min(1D, direction.dot(other.direction(ticks)))));
+            double contact = radius + Math.atan((other.kind == PortDayCycle.SUN ? 30D : 20D) * other.size * 0.25D / 100D);
+            strongest = Math.max(strongest, (float) Math.max(0D, 1D - separation / contact));
+        }
+        return strongest;
+    }
+
+    public static float eclipseAt(java.util.List<PortCelestialBody> bodies, double ticks) {
+        float strongest = 0;
+        for (var body : bodies) if (body.kind == PortDayCycle.SUN && body.direction(ticks).y > 0D)
+            strongest = Math.max(strongest, body.eclipse(bodies, ticks));
+        return strongest;
+    }
+
+    /** Shared client/server-checkable RGB rule; alpha is handled by the renderer. */
+    public int eclipseColor(float eclipse) {
+        int rgb = color < 0 ? 0xffffff : color;
+        float corona = kind == PortDayCycle.SUN ? (float) Math.pow(eclipse, 8D) * 0.8F : 0F;
+        int red = channel(rgb >> 16 & 255, eclipse, corona);
+        int green = channel(rgb >> 8 & 255, eclipse, corona);
+        int blue = channel(rgb & 255, eclipse, corona);
+        return red << 16 | green << 8 | blue;
+    }
+
+    private int channel(int value, float eclipse, float corona) {
+        return Math.round(kind == PortDayCycle.MOON ? value * (1F - eclipse) : value + (255 - value) * corona);
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortDayCycle.java

@@ -19,7 +19,9 @@ import net.minecraft.world.level.Level;
 
 /** Authored native celestial controls. Never mutates the shared clock. */
 public record PortDayCycle(boolean authored, double period, int stoppedTime,
-                           long originTick, int phaseTick, boolean clockwise, int bearing, float sunSize) {
+                           long originTick, int phaseTick, boolean clockwise, int bearing, float sunSize, int bodyMode,
+                           List<PortCelestialBody> bodies) {
+    public static final int PAIRED = 0, SUN = 1, MOON = 2, NONE = 3;
     public static final PortDayCycle NATIVE = new PortDayCycle(false, 1, 0);
     public static final Identifier NORMAL_TIME = Identifier.fromNamespaceAndPath("rivencraft", "celestial/normal_time");
     public static final Codec<PortDayCycle> CODEC = RecordCodecBuilder.create(instance -> instance.group(
@@ -30,20 +32,40 @@ public record PortDayCycle(boolean authored, double period, int stoppedTime,
             Codec.intRange(0, 23999).optionalFieldOf("phase_tick", 0).forGetter(PortDayCycle::phaseTick),
             Codec.BOOL.optionalFieldOf("clockwise", true).forGetter(PortDayCycle::clockwise),
             Codec.intRange(-1, 359).optionalFieldOf("bearing", -1).forGetter(PortDayCycle::bearing),
-            Codec.floatRange(0.25F, 3F).optionalFieldOf("sun_size", 1F).forGetter(PortDayCycle::sunSize)
+            Codec.floatRange(0.25F, 3F).optionalFieldOf("sun_size", 1F).forGetter(PortDayCycle::sunSize),
+            Codec.intRange(0, 3).optionalFieldOf("body_mode", PAIRED).forGetter(PortDayCycle::bodyMode),
+            PortCelestialBody.CODEC.listOf().optionalFieldOf("bodies", List.of()).forGetter(PortDayCycle::bodies)
     ).apply(instance, PortDayCycle::new));
     public static final StreamCodec<RegistryFriendlyByteBuf, PortDayCycle> STREAM_CODEC = StreamCodec.composite(
             ByteBufCodecs.BOOL, PortDayCycle::authored, ByteBufCodecs.DOUBLE, PortDayCycle::period,
             ByteBufCodecs.VAR_INT, PortDayCycle::stoppedTime, ByteBufCodecs.VAR_LONG, PortDayCycle::originTick,
             ByteBufCodecs.VAR_INT, PortDayCycle::phaseTick, ByteBufCodecs.BOOL, PortDayCycle::clockwise,
-            ByteBufCodecs.INT, PortDayCycle::bearing, ByteBufCodecs.FLOAT, PortDayCycle::sunSize, PortDayCycle::new);
+            ByteBufCodecs.INT, PortDayCycle::bearing, ByteBufCodecs.FLOAT, PortDayCycle::sunSize,
+            ByteBufCodecs.VAR_INT, PortDayCycle::bodyMode,
+            PortCelestialBody.STREAM_CODEC.apply(ByteBufCodecs.list()), PortDayCycle::bodies, PortDayCycle::new);
     private static volatile Map<Identifier, PortDayCycle> clientCycles = Map.of();
 
     public PortDayCycle {
+        bodies = List.copyOf(bodies);
         if (!Double.isFinite(period) || period < 0 || period > 2 || stoppedTime < 0 || stoppedTime >= 24000
                 || phaseTick < 0 || phaseTick >= 24000 || bearing < -1 || bearing >= 360
-                || !Float.isFinite(sunSize) || sunSize < 0.25F || sunSize > 3F)
+                || !Float.isFinite(sunSize) || sunSize < 0.25F || sunSize > 3F
+                || bodyMode < PAIRED || bodyMode > NONE
+                || bodyMode == NONE && (!authored || !bodies.isEmpty()))
             throw new IllegalArgumentException("Invalid day cycle");
+        if (bodies.stream().filter(body -> body.kind() == SUN).count() > 10
+                || bodies.stream().filter(body -> body.kind() == MOON).count() > 10)
+            throw new IllegalArgumentException("An Age may have at most ten suns and ten moons");
+    }
+
+    public PortDayCycle(boolean authored, double period, int stoppedTime,
+                        long originTick, int phaseTick, boolean clockwise, int bearing, float sunSize, int bodyMode) {
+        this(authored, period, stoppedTime, originTick, phaseTick, clockwise, bearing, sunSize, bodyMode, List.of());
+    }
+
+    public PortDayCycle(boolean authored, double period, int stoppedTime,
+                        long originTick, int phaseTick, boolean clockwise, int bearing, float sunSize) {
+        this(authored, period, stoppedTime, originTick, phaseTick, clockwise, bearing, sunSize, PAIRED);
     }
 
     public PortDayCycle(boolean authored, double period, int stoppedTime) {
@@ -87,7 +109,14 @@ public record PortDayCycle(boolean authored, double period, int stoppedTime,
     }
 
     public static boolean supports(Identifier page) {
-        return page.equals(NORMAL_TIME) || isPeriod(page) || isPhase(page) || isDirection(page) || isAngle(page) || isSize(page);
+        return isController(page) || isPeriod(page) || isPhase(page) || isDirection(page) || isAngle(page) || isSize(page);
+    }
+
+    public static boolean isController(Identifier page) {
+        return page.getNamespace().equals("rivencraft") && switch (page.getPath()) {
+            case "celestial/normal_time", "celestial/sun", "celestial/moon" -> true;
+            default -> false;
+        };
     }
 
     public static boolean isSize(Identifier page) {
@@ -98,25 +127,74 @@ public record PortDayCycle(boolean authored, double period, int stoppedTime,
     }
 
     public static boolean validWriting(List<Identifier> pages) {
-        int target = pages.indexOf(NORMAL_TIME), periods = 0, phases = 0, directions = 0, angles = 0, sizes = 0;
-        if (target != pages.lastIndexOf(NORMAL_TIME)) return false;
-        for (int i = 0; i < pages.size(); i++) {
-            if (isPeriod(pages.get(i)) && (++periods > 1 || i > target)) return false;
-            if (isPhase(pages.get(i)) && (++phases > 1 || i > target)) return false;
-            if (isDirection(pages.get(i)) && (++directions > 1 || i > target)) return false;
-            if (isAngle(pages.get(i)) && (++angles > 1 || i > target)) return false;
-            if (isSize(pages.get(i)) && (++sizes > 1 || i > target)) return false;
+        int periods = 0, phases = 0, directions = 0, angles = 0, sizes = 0, suns = 0, moons = 0;
+        for (Identifier page : pages) {
+            if (isPeriod(page) && ++periods > 1 || isPhase(page) && ++phases > 1
+                    || isDirection(page) && ++directions > 1 || isAngle(page) && ++angles > 1
+                    || isSize(page) && ++sizes > 1) return false;
+            if (isController(page)) {
+                if (!page.getPath().equals("celestial/moon")) suns++;
+                if (!page.getPath().equals("celestial/sun")) moons++;
+                if (suns > 10 || moons > 10) return false;
+                periods = phases = directions = angles = sizes = 0;
+            }
         }
-        return true;
+        return periods + phases + directions + angles + sizes == 0;
     }
 
     public static PortDayCycle compile(List<Identifier> pages, long seed) {
         return compile(pages, seed, 0);
     }
 
+    /** Creation-only completion. Exact diagnostic fixtures can still use compile. */
+    public static PortDayCycle resolve(List<Identifier> pages, long seed, long nativeTicks) {
+        if (!validWriting(pages) || !PortAgeColors.validNumbers(pages))
+            throw new IllegalArgumentException("Invalid celestial modifier order");
+        if (pages.stream().anyMatch(PortDayCycle::isController)) return compile(pages, seed, nativeTicks);
+        // Match root AgeSkyProfile.random's count draw positions: sky style,
+        // mixed sky color, then independent 0..3 sun and moon counts.
+        var random = new Random(seed ^ 0x534B5950524F464CL);
+        random.nextInt(5);
+        randomColor(random);
+        int suns = random.nextInt(4), moons = random.nextInt(4);
+        var bodies = new java.util.ArrayList<PortCelestialBody>();
+        for (int i = 0; i < suns + moons; i++)
+            bodies.addAll(randomUnmodified(seed, i, nativeTicks, i < suns ? SUN : MOON).bodies);
+        if (bodies.isEmpty()) return new PortDayCycle(true, 1, 0, 0, 0, true, -1, 1F, NONE);
+        var first = bodies.getFirst();
+        return new PortDayCycle(true, first.period(), first.stoppedTime(), first.originTick(), first.phaseTick(),
+                first.clockwise(), first.bearing(), first.size(), first.kind(), bodies);
+    }
+
     public static PortDayCycle compile(List<Identifier> pages, long seed, long nativeTicks) {
-        if (!validWriting(pages)) throw new IllegalArgumentException("Place at most one Length, Phase, Direction, Angle, and Size before Normal Time");
-        if (!pages.contains(NORMAL_TIME)) return NATIVE;
+        if (!validWriting(pages)) throw new IllegalArgumentException("Place at most one of each celestial modifier before its controller; limit ten suns and ten moons");
+        if (pages.stream().filter(PortDayCycle::isController).count() <= 1)
+            return compileOne(pages, seed, nativeTicks, 0);
+        var bodies = new java.util.ArrayList<PortCelestialBody>();
+        PortDayCycle first = null;
+        int start = 0, ordinal = 0;
+        for (int i = 0; i < pages.size(); i++) if (isController(pages.get(i))) {
+            var cycle = compileOne(pages.subList(start, i + 1), seed, nativeTicks, ordinal++);
+            if (first == null) first = cycle;
+            // Prefix retains original page indices for seeded unnumbered colors.
+            int color = PortAgeColors.compile(pages.subList(0, i + 1), seed).celestial();
+            if (!cycle.bodies.isEmpty()) bodies.addAll(cycle.bodies);
+            else {
+                if (cycle.bodyMode != MOON) bodies.add(PortCelestialBody.of(cycle, SUN, color, false));
+                if (cycle.bodyMode != SUN) bodies.add(PortCelestialBody.of(cycle, MOON, color, cycle.bodyMode == PAIRED));
+            }
+            start = i + 1;
+        }
+        return new PortDayCycle(first.authored, first.period, first.stoppedTime, first.originTick,
+                first.phaseTick, first.clockwise, first.bearing, first.sunSize, first.bodyMode, bodies);
+    }
+
+    private static PortDayCycle compileOne(List<Identifier> pages, long seed, long nativeTicks, int ordinal) {
+        var controller = pages.stream().filter(PortDayCycle::isController).findFirst().orElse(null);
+        if (controller == null) return NATIVE;
+        int mode = controller.getPath().equals("celestial/sun") ? SUN
+                : controller.getPath().equals("celestial/moon") ? MOON : PAIRED;
+        if (mode != PAIRED && !hasBodyModifiers(pages)) return randomUnmodified(seed, ordinal, nativeTicks, mode);
         double period = 1;
         Integer phase = null;
         boolean clockwise = true;
@@ -160,7 +238,59 @@ public record PortDayCycle(boolean authored, double period, int stoppedTime,
         int stopped = period == 0 ? phase != null ? phase
                 : new Random(seed ^ 0x4441594359434C45L).nextInt(24000) : 0;
         return new PortDayCycle(true, period, stopped, phase != null ? nativeTicks : 0,
-                phase == null ? 0 : phase, clockwise, bearing, size);
+                phase == null ? 0 : phase, clockwise, bearing, size, mode);
+    }
+
+    private static boolean hasBodyModifiers(List<Identifier> pages) {
+        boolean color = false, controls = false;
+        for (var page : pages) {
+            if (isController(page)) return controls || color;
+            if (PortAgeColors.isColor(page)) color = true;
+            else if (PortSkyStyle.forPage(page) != null || page.equals(PortAgeColors.AMBIENT)) color = false;
+            if (isPeriod(page) || isPhase(page) || isDirection(page) || isAngle(page) || isSize(page)) controls = true;
+        }
+        return false;
+    }
+
+    private static PortDayCycle randomUnmodified(long seed, int ordinal, long nativeTicks, int mode) {
+        // Independent per-controller stream: unrelated terrain/sky/weather pages
+        // cannot reshuffle the bodies. Use root random-Age bounds, not native defaults.
+        var random = new Random(seed ^ 0x43454C4553544941L ^ (ordinal + 1L) * 0x9E3779B97F4A7C15L);
+        double period = random.nextInt(7) == 0 ? 0D : 0.2D + random.nextDouble() * 1.8D;
+        int phase = random.nextInt(24000), bearing = random.nextInt(360);
+        float size = 0.75F + random.nextFloat();
+        boolean clockwise = random.nextBoolean();
+        int color = randomColor(random);
+        var cycle = new PortDayCycle(true, period, period == 0 ? phase : 0, nativeTicks,
+                phase, clockwise, bearing, size, mode);
+        return new PortDayCycle(true, period, cycle.stoppedTime, nativeTicks, phase, clockwise, bearing, size,
+                mode, List.of(PortCelestialBody.of(cycle, mode, color, false)));
+    }
+
+    private static int randomColor(Random random) {
+        return PortAgeColors.randomColor(random, false);
+    }
+
+    public boolean singleBody() { return authored && (bodyMode == SUN || bodyMode == MOON); }
+    public boolean customLight() { return singleBody() || !bodies.isEmpty(); }
+
+    /** Linear authored orbit, as in 1.21.1 Body; zero degrees is Zenith. */
+    public float bodyAngle(long nativeTicks) {
+        return (float) (((time(nativeTicks) - 6000D) % 24000D) * (360D / 24000D));
+    }
+
+    public float bodyLight(long nativeTicks) {
+        if (bodyMode == NONE) return 0;
+        if (!bodies.isEmpty()) {
+            float sun = 0, moon = 0;
+            for (var body : bodies) {
+                if (body.kind() == SUN) sun += body.light(nativeTicks) * (1F - 0.85F * body.eclipse(bodies, nativeTicks));
+                else moon += body.light(nativeTicks);
+            }
+            return Math.min(1F, sun > 0 ? sun : moon);
+        }
+        float altitude = Math.max(0F, (float) Math.cos(Math.toRadians(bodyAngle(nativeTicks))));
+        return altitude * (bodyMode == MOON ? 0.18F : 1F);
     }
 
     public long ticks(long nativeTicks) {

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortFeatureChunkGenerator.java

@@ -113,7 +113,7 @@ public final class PortFeatureChunkGenerator extends ChunkGenerator {
     }
     @Override public ChunkGeneratorStructureState createState(HolderLookup<StructureSet> sets,
                                                                RandomState random, long seed) {
-        if (hasStructurePages()) {
+        if (controlsStructures()) {
             var lookup = PortStructurePages.filtered(sets, terrainFeatures.structures(), getBiomeSource());
             var planning = PortStructurePages.planningBiomes(getBiomeSource(), sets, terrainFeatures.structures());
             if (base instanceof PortFlatChunkGenerator || base instanceof net.minecraft.world.level.levelgen.FlatLevelSource)
@@ -124,13 +124,13 @@ public final class PortFeatureChunkGenerator extends ChunkGenerator {
         return base.createState(sets, random, seed);
     }
 
-    private boolean hasStructurePages() {
-        return terrainFeatures != null && !terrainFeatures.structures().isEmpty();
+    private boolean controlsStructures() {
+        return terrainFeatures != null && (terrainFeatures.structureControl() || !terrainFeatures.structures().isEmpty());
     }
     @Override public void createStructures(RegistryAccess registries, ChunkGeneratorStructureState state,
                                            StructureManager structures, ChunkAccess chunk,
                                            StructureTemplateManager templates, ResourceKey<Level> dimension) {
-        if (hasStructurePages()) super.createStructures(registries, state, structures, chunk, templates, dimension);
+        if (controlsStructures()) super.createStructures(registries, state, structures, chunk, templates, dimension);
         else base.createStructures(registries, state, structures, chunk, templates, dimension);
     }
     @Override public void createReferences(WorldGenLevel level, StructureManager structures, ChunkAccess chunk) {

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortRandomAgeSelection.java

@@ -19,30 +19,18 @@ public final class PortRandomAgeSelection {
     public static Selection select(MinecraftServer server, long seed) {
         // Match the 1.21.1 Legacy-rank choices: Standard and Flat are common;
         // the other terrain families are rarer. The sorted order is deliberate.
-        PortAgeTerrain terrain = weighted(new Random(seed ^ 0x5445525241494E4CL),
-                List.of(PortAgeTerrain.AMPLIFIED, PortAgeTerrain.CAVE, PortAgeTerrain.FLAT,
-                        PortAgeTerrain.ISLAND, PortAgeTerrain.STANDARD, PortAgeTerrain.VOID),
-                new int[]{1, 1, 5, 1, 6, 1});
+        PortAgeTerrain terrain = terrain(seed);
         if (terrain == PortAgeTerrain.VOID)
             return new Selection(terrain, new PortBiomePlan(PortBiomePlan.Distribution.SINGLE,
                     List.of(Identifier.withDefaultNamespace("the_void"))));
 
-        PortBiomePlan.Distribution distribution = weighted(new Random(seed ^ 0x524956454E435241L),
-                List.of(PortBiomePlan.Distribution.NATIVE, PortBiomePlan.Distribution.SINGLE,
-                        PortBiomePlan.Distribution.MEDIUM, PortBiomePlan.Distribution.TILED,
-                        PortBiomePlan.Distribution.GRID, PortBiomePlan.Distribution.TINY,
-                        PortBiomePlan.Distribution.SMALL, PortBiomePlan.Distribution.LARGE,
-                        PortBiomePlan.Distribution.HUGE),
-                new int[]{3, 3, 3, 1, 1, 1, 1, 1, 1});
+        PortBiomePlan.Distribution distribution = distribution(seed);
         List<Identifier> eligible = eligibleBiomes(server, terrain);
         if (eligible.size() < 2 && distribution != PortBiomePlan.Distribution.NATIVE)
             distribution = PortBiomePlan.Distribution.SINGLE;
-        // 26.3 has no native multi-cave biome source; choose a seeded Cave
-        // biome rather than silently using Lush Caves for every random Age.
-        if (terrain == PortAgeTerrain.CAVE && distribution == PortBiomePlan.Distribution.NATIVE)
-            distribution = PortBiomePlan.Distribution.SINGLE;
         if (distribution == PortBiomePlan.Distribution.NATIVE)
-            return new Selection(terrain, new PortBiomePlan(distribution, List.of()));
+            return new Selection(terrain, new PortBiomePlan(distribution,
+                    terrain == PortAgeTerrain.CAVE ? eligible : List.of()));
 
         int count = distribution == PortBiomePlan.Distribution.SINGLE ? 1 : 2;
         if (count > 1) {
@@ -54,13 +42,30 @@ public final class PortRandomAgeSelection {
         return new Selection(terrain, new PortBiomePlan(distribution, shuffled.subList(0, count)));
     }
 
-    private static List<Identifier> eligibleBiomes(MinecraftServer server, PortAgeTerrain terrain) {
+    public static List<PortAgeTerrain> terrains() {
+        return List.of(PortAgeTerrain.AMPLIFIED, PortAgeTerrain.CAVE, PortAgeTerrain.FLAT,
+                PortAgeTerrain.ISLAND, PortAgeTerrain.STANDARD, PortAgeTerrain.VOID);
+    }
+
+    public static PortAgeTerrain terrain(long seed) {
+        return weighted(new Random(seed ^ 0x5445525241494E4CL), terrains(), new int[]{1, 1, 5, 1, 6, 1});
+    }
+
+    /** First AgeTraits draw in 1.21.1; shared by random and partly authored Ages. */
+    public static PortBiomePlan.Distribution distribution(long seed) {
+        return weighted(new Random(seed ^ 0x524956454E435241L),
+                List.of(PortBiomePlan.Distribution.NATIVE, PortBiomePlan.Distribution.SINGLE,
+                        PortBiomePlan.Distribution.MEDIUM, PortBiomePlan.Distribution.TILED,
+                        PortBiomePlan.Distribution.GRID, PortBiomePlan.Distribution.TINY,
+                        PortBiomePlan.Distribution.SMALL, PortBiomePlan.Distribution.LARGE,
+                        PortBiomePlan.Distribution.HUGE),
+                new int[]{3, 3, 3, 1, 1, 1, 1, 1, 1});
+    }
+
+    public static List<Identifier> eligibleBiomes(MinecraftServer server, PortAgeTerrain terrain) {
+        if (terrain == PortAgeTerrain.VOID) return List.of(Identifier.withDefaultNamespace("the_void"));
         if (terrain == PortAgeTerrain.CAVE) {
-            List<Identifier> caves = server.registryAccess().lookupOrThrow(Registries.BIOME).listElements()
-                    .filter(PortRegistryPages::isCaveBiome)
-                    .map(holder -> holder.key().identifier())
-                    .sorted().toList();
-            return caves.isEmpty() ? List.of(Identifier.withDefaultNamespace("lush_caves")) : caves;
+            return caveBiomes(server.registryAccess());
         }
         List<Identifier> surface = server.overworld().getChunkSource().getGenerator().getBiomeSource()
                 .possibleBiomes().stream().flatMap(holder -> holder.unwrapKey().stream())
@@ -68,6 +73,12 @@ public final class PortRandomAgeSelection {
         return surface.isEmpty() ? List.of(Identifier.withDefaultNamespace("plains")) : surface;
     }
 
+    public static List<Identifier> caveBiomes(net.minecraft.core.HolderLookup.Provider registries) {
+        var caves = registries.lookupOrThrow(Registries.BIOME).listElements()
+                .filter(PortRegistryPages::isCaveBiome).map(holder -> holder.key().identifier()).sorted().toList();
+        return caves.isEmpty() ? List.of(Identifier.withDefaultNamespace("lush_caves")) : caves;
+    }
+
     static <T> T weighted(Random random, List<T> choices, int[] weights) {
         int total = 0;
         for (int weight : weights) total += weight;

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortRandomFeatureSelection.java

@@ -0,0 +1,85 @@
+package net.dnorberg.rivencraft.age;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+import net.dnorberg.rivencraft.writing.PortAuthoredWriting;
+import net.dnorberg.rivencraft.writing.PortRegistryPages;
+import net.minecraft.resources.Identifier;
+
+/** Frozen page-free material features and rare formations from 1.21.1. */
+public final class PortRandomFeatureSelection {
+    private PortRandomFeatureSelection() {}
+    public record Selection(PortRockPlan rocks, PortLakePlan lakes, PortTerrainFeaturePlan terrain, int dungeons) {}
+
+    public static Selection select(net.minecraft.server.MinecraftServer server, long seed,
+                                    PortAgeTerrain terrain, PortBiomePlan biomes) {
+        var base = select(seed, terrain);
+        var structures = PortRandomStructureSelection.select(server, seed, terrain, biomes);
+        var plan = base.terrain();
+        plan = plan == null ? new PortTerrainFeaturePlan(List.of(), false, 0, false, structures.structures(), List.of(), true)
+                    : new PortTerrainFeaturePlan(plan.choices(), plan.skylands(), plan.denseOres(), plan.starFissures(),
+                            structures.structures(), plan.carvers(), true);
+        return new Selection(base.rocks(), base.lakes(), plan, structures.dungeons());
+    }
+
+    public static Selection select(long seed, PortAgeTerrain terrain) {
+        var random = new Random(seed ^ 0x4D4154455249414CL);
+        int count = random.nextInt(3);
+        var terrainPage = id("terrain/" + terrain.name().toLowerCase(java.util.Locale.ROOT));
+        var candidates = new ArrayList<PortRankedChoice.Option<Identifier>>();
+        for (String name : List.of("rocks", "floating_islands", "tendrils", "spheres", "spikes", "obelisks",
+                "surface_lakes", "deep_lakes", "lava_lakes")) {
+            var page = id("feature/" + name);
+            if (PortAuthoredWriting.supports(List.of(terrainPage, page)))
+                candidates.add(new PortRankedChoice.Option<>(page, rank(name)));
+        }
+        var pages = new ArrayList<Identifier>();
+        pages.add(terrainPage);
+        List<Identifier> solids = PortRegistryPages.solidMaterialIds(), fluids = PortRegistryPages.fluidMaterialIds();
+        for (int selected = 0; selected < count && !candidates.isEmpty();) {
+            Identifier feature = PortRankedChoice.choose(random, candidates);
+            candidates.removeIf(option -> option.value().equals(feature));
+            var materials = PortLakePlan.isLake(feature) ? fluids : solids;
+            if (materials.isEmpty()) continue;
+            pages.add(PortRegistryPages.blockPageId(materials.get(random.nextInt(materials.size()))));
+            pages.add(feature);
+            selected++;
+        }
+        if (terrain != PortAgeTerrain.FLAT && terrain != PortAgeTerrain.VOID
+                && Math.floorMod(mix(seed ^ 0x534B594C414E4453L), 8) == 0)
+            pages.add(PortTerrainFeaturePlan.SKYLANDS);
+        if (terrain != PortAgeTerrain.CAVE && terrain != PortAgeTerrain.VOID && random.nextInt(10) == 0)
+            pages.add(PortTerrainFeaturePlan.CRYSTAL_FORMATIONS);
+        if (randomStarFissure(seed)) pages.add(PortTerrainFeaturePlan.STAR_FISSURES);
+        return new Selection(PortAuthoredWriting.rockPlan(pages, seed), PortAuthoredWriting.lakePlan(pages, seed),
+                PortAuthoredWriting.terrainFeaturePlan(pages, seed), 0);
+    }
+
+    private static int rank(String name) {
+        return switch (name) {
+            case "surface_lakes", "deep_lakes" -> 1;
+            case "lava_lakes" -> 2;
+            case "spheres", "spikes", "obelisks" -> 3;
+            default -> 4;
+        };
+    }
+
+    private static boolean randomStarFissure(long seed) {
+        var random = new Random(mix(seed ^ 0x535441524752414DL));
+        for (int step = 0; step < 27; step++) {
+            int branch = random.nextInt(5);
+            if (branch == 0) return false;
+            if (random.nextInt(9) == 0) return true;
+            if (branch == 1) return false;
+        }
+        return false;
+    }
+
+    private static Identifier id(String path) { return Identifier.fromNamespaceAndPath("rivencraft", path); }
+    private static long mix(long value) {
+        value = (value ^ value >>> 30) * 0xBF58476D1CE4E5B9L;
+        value = (value ^ value >>> 27) * 0x94D049BB133111EBL;
+        return value ^ value >>> 31;
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortRandomStructureSelection.java

@@ -0,0 +1,69 @@
+package net.dnorberg.rivencraft.age;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.resources.Identifier;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.world.level.dimension.LevelStem;
+
+/** Creation-only structure completion, adapted from 1.21.1 AgeStructureSelection. */
+public final class PortRandomStructureSelection {
+    private static final Identifier DUNGEONS = page("dungeons");
+    private PortRandomStructureSelection() {}
+    public record Selection(int dungeons, List<Identifier> structures) {
+        public Selection { structures = List.copyOf(structures); }
+    }
+
+    public static Selection select(MinecraftServer server, long seed, PortAgeTerrain terrain, PortBiomePlan plan) {
+        Set<Identifier> biomes = actualBiomes(server, terrain, plan);
+        var eligible = new ArrayList<PortRankedChoice.Option<Identifier>>();
+        for (String name : List.of("dungeons", "mineshafts", "nether_fortresses", "strongholds", "villages",
+                "trial_chambers", "bastions", "buried_treasure", "shipwrecks", "ocean_ruins", "pillager_outposts",
+                "ruined_portals", "nether_fossils", "ancient_cities", "trail_ruins", "abandoned_camps")) {
+            Identifier feature = page(name);
+            boolean allowed = feature.equals(DUNGEONS)
+                    ? net.dnorberg.rivencraft.writing.PortAuthoredWriting.supports(List.of(
+                            Identifier.fromNamespaceAndPath("rivencraft", "terrain/" + terrain.name().toLowerCase(java.util.Locale.ROOT)), feature))
+                        && server.registryAccess().lookupOrThrow(Registries.PLACED_FEATURE)
+                            .get(ResourceKey.create(Registries.PLACED_FEATURE,
+                                    Identifier.fromNamespaceAndPath("rivencraft", "dungeons"))).isPresent()
+                    : PortStructurePages.randomEligible(feature, terrain, biomes, server.registryAccess());
+            if (allowed) eligible.add(new PortRankedChoice.Option<>(feature, rank(name)));
+        }
+        var random = new Random(seed ^ 0x5354525543545552L);
+        int count = random.nextInt(3), dungeons = 0;
+        var structures = new ArrayList<Identifier>();
+        for (int selected = 0; selected < count && !eligible.isEmpty(); selected++) {
+            var feature = PortRankedChoice.choose(random, eligible);
+            if (feature.equals(DUNGEONS)) dungeons++;
+            else structures.add(feature);
+            eligible.removeIf(option -> option.value().equals(feature));
+        }
+        return new Selection(dungeons, structures);
+    }
+
+    private static Set<Identifier> actualBiomes(MinecraftServer server, PortAgeTerrain terrain, PortBiomePlan plan) {
+        if (plan != null && !plan.biomes().isEmpty())
+            return Set.copyOf(plan.biomes());
+        if (terrain == PortAgeTerrain.FLAT) return Set.of(Identifier.withDefaultNamespace("plains"));
+        if (terrain == PortAgeTerrain.VOID) return Set.of(Identifier.withDefaultNamespace("the_void"));
+        if (terrain == PortAgeTerrain.CAVE) return Set.of(Identifier.withDefaultNamespace("lush_caves"));
+        return server.registryAccess().lookupOrThrow(Registries.LEVEL_STEM).getOrThrow(LevelStem.OVERWORLD)
+                .value().generator().getBiomeSource().possibleBiomes().stream()
+                .flatMap(holder -> holder.unwrapKey().stream()).map(key -> key.identifier())
+                .collect(java.util.stream.Collectors.toUnmodifiableSet());
+    }
+
+    private static int rank(String name) {
+        return switch (name) {
+            case "villages", "strongholds", "mineshafts" -> 1;
+            case "dungeons", "nether_fortresses" -> 2;
+            default -> 3;
+        };
+    }
+    private static Identifier page(String name) { return Identifier.fromNamespaceAndPath("rivencraft", "feature/" + name); }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortRankedChoice.java

@@ -0,0 +1,36 @@
+package net.dnorberg.rivencraft.age;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Random;
+
+/** The 1.21.1 LegacyRankChoice rule, retained for seeded grammar completion. */
+final class PortRankedChoice {
+    private PortRankedChoice() {}
+    record Option<T>(T value, int rank) {}
+
+    static <T> T choose(Random random, List<Option<T>> options) {
+        if (options.isEmpty()) throw new IllegalArgumentException("No ranked choices");
+        var counts = new HashMap<Integer, Integer>();
+        int highest = 0;
+        for (var option : options) {
+            counts.merge(option.rank(), 1, Integer::sum);
+            highest = Math.max(highest, option.rank());
+        }
+        var weights = new HashMap<Integer, Integer>();
+        int weight = 1, previousTotal = 0;
+        for (int rank = highest; rank >= 0; rank--) {
+            int count = counts.getOrDefault(rank, 0);
+            if (weight != 1 && count > 0) weight = Math.max(weight, previousTotal / count + 1);
+            weights.put(rank, weight);
+            previousTotal = count * weight;
+            weight++;
+        }
+        int ticket = random.nextInt(options.stream().mapToInt(option -> weights.get(option.rank())).sum());
+        for (var option : options) {
+            ticket -= weights.get(option.rank());
+            if (ticket < 0) return option.value();
+        }
+        throw new IllegalStateException("Ranked choice ticket was not consumed");
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortSkyStyle.java

@@ -31,11 +31,20 @@ public enum PortSkyStyle {
                         ? OVERWORLD : random(seed));
     }
 
+    /** Nether-style Ages use their fog clear color as the visible backdrop. */
+    public static float fogShade(net.minecraft.world.level.Level level) {
+        boolean nether = level.dimensionTypeRegistration().unwrapKey().map(key ->
+                key.identifier().getNamespace().equals("rivencraft")
+                        && key.identifier().getPath().endsWith("_sky_nether")).orElse(false);
+        var cycle = PortDayCycle.forLevel(level);
+        return nether && !cycle.bodies().isEmpty()
+                ? 1F - 0.65F * PortCelestialBody.eclipseAt(cycle.bodies(), PortDayCycle.nativeTicks(level)) : 1F;
+    }
+
     private static boolean isCelestial(Identifier page) {
         if (!page.getNamespace().equals(Rivencraft.MOD_ID)) return false;
         return switch (page.getPath()) {
-            // Only Overworld currently draws bodies in this port. Recognize the
-            // Sun/Moon intentions too, without marking those pages implemented.
+            // Preserve the established compatible-default rule for written controllers.
             case "celestial/normal_time", "celestial/sun", "celestial/moon" -> true;
             default -> false;
         };

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortStructurePages.java

@@ -88,6 +88,31 @@ public final class PortStructurePages {
                         .orElseThrow(() -> new IllegalArgumentException("Missing structure set for " + page)));
     }
 
+    /** Random choices need at least one normally eligible biome; authored pages may override it. */
+    public static boolean randomEligible(Identifier page, PortAgeTerrain terrain, Set<Identifier> biomes,
+                                         HolderLookup.Provider registries) {
+        if (!supportsTerrain(page, terrain)) return false;
+        var set = registries.lookupOrThrow(Registries.STRUCTURE_SET)
+                .get(ResourceKey.create(Registries.STRUCTURE_SET, SETS.get(page)));
+        if (set.isEmpty()) return false;
+        var compatible = compatibleBiomes(set.get().value());
+        return compatible.isEmpty() || biomes.stream().anyMatch(compatible::contains);
+    }
+
+    public static Set<Identifier> compatibleBiomes(Identifier page, HolderLookup.Provider registries) {
+        if (!supports(page)) return Set.of();
+        return registries.lookupOrThrow(Registries.STRUCTURE_SET)
+                .get(ResourceKey.create(Registries.STRUCTURE_SET, SETS.get(page)))
+                .map(holder -> compatibleBiomes(holder.value())).orElse(Set.of());
+    }
+
+    private static Set<Identifier> compatibleBiomes(StructureSet set) {
+        return set.structures().stream()
+                .flatMap(entry -> entry.structure().value().biomes().stream())
+                .flatMap(holder -> holder.unwrapKey().stream()).map(key -> key.identifier())
+                .collect(java.util.stream.Collectors.toUnmodifiableSet());
+    }
+
     private static Map<Identifier, Integer> enabled(List<Identifier> pages) {
         Map<Identifier, Integer> result = new HashMap<>();
         for (Identifier page : pages) result.merge(SETS.get(page), 1, Integer::sum);

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/PortTerrainFeaturePlan.java

@@ -9,7 +9,8 @@ import net.minecraft.resources.Identifier;
 
 /** Frozen terrain filters and ordered solid/surface features for an Age. */
 public record PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int denseOres,
-                                     boolean starFissures, List<Identifier> structures, List<Identifier> carvers) {
+                                     boolean starFissures, List<Identifier> structures, List<Identifier> carvers,
+                                     boolean structureControl) {
     public static final Identifier FLOATING_ISLANDS = Identifier.fromNamespaceAndPath(
             Rivencraft.MOD_ID, "feature/floating_islands");
     public static final Identifier TENDRILS = Identifier.fromNamespaceAndPath(Rivencraft.MOD_ID, "feature/tendrils");
@@ -30,7 +31,8 @@ public record PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int
                     .forGetter(PortTerrainFeaturePlan::denseOres),
             Codec.BOOL.optionalFieldOf("star_fissures", false).forGetter(PortTerrainFeaturePlan::starFissures),
             Identifier.CODEC.listOf().optionalFieldOf("structures", List.of()).forGetter(PortTerrainFeaturePlan::structures),
-            Identifier.CODEC.listOf().optionalFieldOf("carvers", List.of()).forGetter(PortTerrainFeaturePlan::carvers)
+            Identifier.CODEC.listOf().optionalFieldOf("carvers", List.of()).forGetter(PortTerrainFeaturePlan::carvers),
+            Codec.BOOL.optionalFieldOf("structure_control", false).forGetter(PortTerrainFeaturePlan::structureControl)
     ).apply(instance, PortTerrainFeaturePlan::new));
 
     public record Choice(Identifier page, Identifier material) {
@@ -55,7 +57,7 @@ public record PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int
         PortCarverPages.validateCounts(carvers);
         if (denseOres < 0 || denseOres > MAX_PER_FEATURE)
             throw new IllegalArgumentException("Dense Ores permits at most 32 occurrences");
-        if (choices.isEmpty() && !skylands && denseOres == 0 && !starFissures && structures.isEmpty() && carvers.isEmpty())
+        if (choices.isEmpty() && !skylands && denseOres == 0 && !starFissures && structures.isEmpty() && carvers.isEmpty() && !structureControl)
             throw new IllegalArgumentException("Terrain feature plan must not be empty");
         var counts = new HashMap<Identifier, Integer>();
         for (Choice choice : choices) {
@@ -64,6 +66,11 @@ public record PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int
         }
     }
 
+    public PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int denseOres,
+                                 boolean starFissures, List<Identifier> structures, List<Identifier> carvers) {
+        this(choices, skylands, denseOres, starFissures, structures, carvers, false);
+    }
+
     public PortTerrainFeaturePlan(List<Choice> choices, boolean skylands, int denseOres,
                                  boolean starFissures, List<Identifier> structures) {
         this(choices, skylands, denseOres, starFissures, structures, List.of());

ports/mc263/src/main/java/net/dnorberg/rivencraft/age/RuntimeAgeBackend.java

@@ -366,15 +366,14 @@ public final class RuntimeAgeBackend {
     }
 
     private static BiomeSource authoredBiomeSource(MinecraftServer server, PortBiomePlan plan, long seed) {
-        if (plan.distribution() == PortBiomePlan.Distribution.NATIVE)
-            throw new IllegalArgumentException("Native biome distribution has no authored source");
         var registry = server.registryAccess().lookupOrThrow(Registries.BIOME);
         List<Holder<Biome>> biomes = plan.biomes().stream().map(id ->
                 (Holder<Biome>) registry.get(ResourceKey.create(Registries.BIOME, id))
                         .orElseThrow(() -> new IllegalArgumentException("Unknown authored biome: " + id)))
                 .toList();
         return switch (plan.distribution()) {
-            case NATIVE -> throw new IllegalStateException("Native is not an override");
+            case NATIVE -> biomes.size() == 1 ? new FixedBiomeSource(biomes.getFirst())
+                    : new PortScaledBiomeSource(HolderSet.direct(biomes), seed, 0);
             case SINGLE -> new FixedBiomeSource(biomes.getFirst());
             case TILED, GRID -> new CheckerboardColumnBiomeSource(HolderSet.direct(biomes),
                     plan.distribution() == PortBiomePlan.Distribution.GRID ? 0 : 4);
@@ -399,9 +398,12 @@ public final class RuntimeAgeBackend {
                                     PortAgeColors colors, PortDayCycle dayCycle) {
         ResourceKey<Level> key = ResourceKey.create(Registries.DIMENSION, id);
         if (server.getLevel(key) != null) throw new IllegalArgumentException("Level already loaded: " + id);
+        if (biomePlan != null && biomePlan.distribution() == PortBiomePlan.Distribution.NATIVE
+                && !biomePlan.biomes().isEmpty() && terrain != PortAgeTerrain.CAVE)
+            throw new IllegalArgumentException("Only Native Cave terrain may carry an explicit native biome pool");
 
         // Noise terrains reuse the Overworld biome source unless a
-        // non-Native authored distribution replaces it.
+        // non-Native authored distribution or a frozen Native Cave pool replaces it.
         // LevelStem.seedOverride controls chunk random state and getSeed().
         LevelStem overworldStem = server.registryAccess().lookupOrThrow(Registries.LEVEL_STEM)
                 .getValue(LevelStem.OVERWORLD);
@@ -453,7 +455,8 @@ public final class RuntimeAgeBackend {
                         throw new IllegalArgumentException("Cave terrain requires a Cave or Nether biome: " + biomeId);
                 }
             }
-            if (biomePlan != null && biomePlan.distribution() != PortBiomePlan.Distribution.NATIVE) {
+            if (biomePlan != null && (biomePlan.distribution() != PortBiomePlan.Distribution.NATIVE
+                    || terrain == PortAgeTerrain.CAVE && !biomePlan.biomes().isEmpty())) {
                 source = authoredBiomeSource(server, biomePlan, seed);
             }
             var settings = switch (terrain) {
@@ -465,7 +468,7 @@ public final class RuntimeAgeBackend {
                 case CAVE -> dryCaveSettings(server);
                 case FLAT, VOID -> throw new IllegalStateException("Flat terrain should use FlatLevelSource");
             };
-            generator = new NoiseBasedChunkGenerator(source, settings);
+            generator = new NoiseBasedChunkGenerator(source, PortBiomeMaterialRules.apply(server.registryAccess(), settings.value()));
         }
         if (rocks != null || vegetation != null || dungeons > 0 || lakes != null || terrainFeatures != null)
             generator = new PortFeatureChunkGenerator(generator, rocks, vegetation, dungeons, lakes, terrainFeatures, seed);

ports/mc263/src/main/java/net/dnorberg/rivencraft/client/PortCelestialDiscs.java

@@ -0,0 +1,85 @@
+package net.dnorberg.rivencraft.client;
+
+import com.mojang.blaze3d.systems.RenderSystem;
+import com.mojang.blaze3d.vertex.BufferBuilder;
+import com.mojang.blaze3d.vertex.ByteBufferBuilder;
+import com.mojang.blaze3d.vertex.DefaultVertexFormat;
+import com.mojang.renderpearl.api.buffers.GpuBuffer;
+import com.mojang.renderpearl.api.commands.RenderPass;
+import com.mojang.renderpearl.api.pipeline.BlendFunction;
+import com.mojang.renderpearl.api.pipeline.ColorTargetState;
+import com.mojang.renderpearl.api.pipeline.PrimitiveTopology;
+import com.mojang.renderpearl.api.pipeline.RenderPipeline;
+import java.util.IdentityHashMap;
+import java.util.Map;
+import net.dnorberg.rivencraft.Rivencraft;
+import net.minecraft.client.renderer.RenderPipelines;
+import net.minecraft.client.renderer.texture.TextureAtlas;
+import net.minecraft.client.renderer.texture.TextureAtlasSprite;
+import net.minecraft.resources.Identifier;
+import net.minecraft.world.level.MoonPhase;
+import net.neoforged.api.distmarker.Dist;
+import net.neoforged.bus.api.SubscribeEvent;
+import net.neoforged.fml.common.EventBusSubscriber;
+import net.neoforged.neoforge.client.event.RegisterRenderPipelinesEvent;
+import org.joml.Matrix4f;
+import org.joml.Vector4f;
+
+/** Legacy's opaque central disc, separate from the native transparent glow. */
+@EventBusSubscriber(modid = Rivencraft.MOD_ID, value = Dist.CLIENT)
+public final class PortCelestialDiscs implements AutoCloseable {
+    private static final Identifier SUN = Identifier.withDefaultNamespace("sun");
+    private static final RenderPipeline CORE = RenderPipelines.CELESTIAL.toBuilder()
+            .withLocation(Identifier.fromNamespaceAndPath(Rivencraft.MOD_ID, "pipeline/celestial_core"))
+            .withColorTargetState(new ColorTargetState(BlendFunction.TRANSLUCENT)).build();
+    private final Map<TextureAtlasSprite, GpuBuffer> cores = new IdentityHashMap<>();
+    private TextureAtlasSprite atlasGeneration;
+
+    @SubscribeEvent public static void register(RegisterRenderPipelinesEvent event) { event.registerPipeline(CORE); }
+
+    public void draw(RenderPass pass, TextureAtlas atlas, boolean moon, MoonPhase phase,
+                     Matrix4f transform, int color, float alpha) {
+        if (alpha <= 0) return;
+        var generation = atlas.getSprite(SUN);
+        if (generation != atlasGeneration) {
+            close();
+            atlasGeneration = generation;
+        }
+        var sprite = moon ? atlas.getSprite(Identifier.withDefaultNamespace("moon/" + phase.getSerializedName())) : generation;
+        var buffer = cores.computeIfAbsent(sprite, ignored -> build(sprite, moon));
+        var indices = RenderSystem.getSequentialBuffer(PrimitiveTopology.QUADS);
+        var indexBuffer = indices.getBuffer(6);
+        var rgb = net.dnorberg.rivencraft.age.PortAgeColors.vector(color);
+        var uniforms = RenderSystem.getDynamicUniforms().writeTransform(transform, new Vector4f(rgb, alpha));
+        pass.setPipeline(RenderSystem.getCompiledPipeline(CORE));
+        RenderSystem.bindDefaultUniforms(pass);
+        pass.setUniform("DynamicTransforms", uniforms);
+        pass.setUniform("Sampler0", atlas.getTextureView(), atlas.getSampler());
+        pass.setVertexBuffer(0, buffer.slice());
+        pass.setIndexBuffer(indexBuffer, indices.type());
+        pass.drawIndexed(6, 1, 0, 0, 0);
+    }
+
+    private static GpuBuffer build(TextureAtlasSprite sprite, boolean moon) {
+        var format = DefaultVertexFormat.POSITION_TEX;
+        try (var bytes = ByteBufferBuilder.exactlySized(4 * format.getVertexSize())) {
+            var builder = new BufferBuilder(bytes, PrimitiveTopology.QUADS, format);
+            // Same 8/32 central area as root's ordinary-alpha second pass.
+            float u0 = sprite.getU(0.375F), u1 = sprite.getU(0.625F);
+            float v0 = sprite.getV(0.375F), v1 = sprite.getV(0.625F);
+            builder.addVertex(-0.25F, 0, -0.25F).setUv(moon ? u1 : u0, moon ? v1 : v0);
+            builder.addVertex(0.25F, 0, -0.25F).setUv(moon ? u0 : u1, moon ? v1 : v0);
+            builder.addVertex(0.25F, 0, 0.25F).setUv(moon ? u0 : u1, moon ? v0 : v1);
+            builder.addVertex(-0.25F, 0, 0.25F).setUv(moon ? u1 : u0, moon ? v0 : v1);
+            try (var mesh = builder.buildOrThrow()) {
+                return RenderSystem.getDevice().createBuffer(() -> "Rivencraft celestial core", 40, mesh.vertexBuffer());
+            }
+        }
+    }
+
+    @Override public void close() {
+        cores.values().forEach(GpuBuffer::close);
+        cores.clear();
+        atlasGeneration = null;
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/client/StaticSkyState.java

@@ -2,6 +2,11 @@ package net.dnorberg.rivencraft.client;
 
 /** Carries extracted sky presentation values without live-world reads during drawing. */
 public interface StaticSkyState {
+    int rivencraft$bodyOverlay();
+    void rivencraft$bodyOverlay(int mode);
+    record Body(int kind, float angle, int bearing, float size, int color, float eclipse) {}
+    java.util.List<Body> rivencraft$bodies();
+    void rivencraft$bodies(java.util.List<Body> bodies);
     long rivencraft$staticFrame();
     void rivencraft$staticFrame(long frame);
     int rivencraft$skyTint();
@@ -10,4 +15,8 @@ public interface StaticSkyState {
     void rivencraft$orbitBearing(int bearing);
     float rivencraft$sunSize();
     void rivencraft$sunSize(float size);
+    int rivencraft$celestialTint();
+    void rivencraft$celestialTint(int color);
+    int rivencraft$bodyMode();
+    void rivencraft$bodyMode(int mode);
 }

ports/mc263/src/main/java/net/dnorberg/rivencraft/mixin/AgeColorAttributesMixin.java

@@ -22,7 +22,9 @@ public class AgeColorAttributesMixin {
         });
         builder.addTimeBasedLayer(EnvironmentAttributes.FOG_COLOR, (base, tick) -> {
             int rgb = PortAgeColors.forLevel(level).sky();
-            return rgb < 0 ? base : PortAgeColors.vector(rgb);
+            var color = rgb < 0 ? base : PortAgeColors.vector(rgb);
+            float shade = net.dnorberg.rivencraft.age.PortSkyStyle.fogShade(level);
+            return shade == 1F ? color : new org.joml.Vector3f(color).mul(shade);
         });
         builder.addTimeBasedLayer(EnvironmentAttributes.AMBIENT_LIGHT_COLOR, (base, tick) -> {
             int rgb = PortAgeColors.forLevel(level).ambient();

ports/mc263/src/main/java/net/dnorberg/rivencraft/mixin/AgeDayTimelineMixin.java

@@ -2,6 +2,7 @@ package net.dnorberg.rivencraft.mixin;
 
 import net.dnorberg.rivencraft.age.PortDayCycle;
 import net.minecraft.world.attribute.EnvironmentAttributeSystem;
+import net.minecraft.world.attribute.EnvironmentAttributes;
 import net.minecraft.world.attribute.WeatherAttributes;
 import net.minecraft.world.level.Level;
 import org.spongepowered.asm.mixin.Mixin;
@@ -11,6 +12,30 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 @Mixin(EnvironmentAttributeSystem.Builder.class)
 public class AgeDayTimelineMixin {
+    @Inject(method = "addDefaultLayers", at = @At("RETURN"))
+    private void rivencraft$singleBody(Level level, CallbackInfoReturnable<EnvironmentAttributeSystem.Builder> cir) {
+        var id = level.dimension().identifier();
+        if (!id.getNamespace().equals("rivencraft") || !id.getPath().startsWith("age/")) return;
+        var builder = cir.getReturnValue();
+        builder.addTimeBasedLayer(EnvironmentAttributes.SUN_ANGLE, (base, tick) -> {
+            var cycle = PortDayCycle.forLevel(level);
+            return cycle.singleBody() ? cycle.bodyAngle(PortDayCycle.nativeTicks(level)) : base;
+        });
+        builder.addTimeBasedLayer(EnvironmentAttributes.MOON_ANGLE, (base, tick) -> {
+            var cycle = PortDayCycle.forLevel(level);
+            return cycle.singleBody() ? cycle.bodyAngle(PortDayCycle.nativeTicks(level)) : base;
+        });
+        builder.addTimeBasedLayer(EnvironmentAttributes.SKY_LIGHT_LEVEL, (base, tick) -> {
+            var cycle = PortDayCycle.forLevel(level);
+            if (!cycle.customLight()) return base;
+            // Match root AgeSkyProfile.lightAt and LevelSkyBrightnessMixin's
+            // single skylight channel. Bright/Dark and no-skylight geometry remain separate.
+            float weather = (1F - level.getRainLevel(1F) * 5F / 16F)
+                    * (1F - level.getThunderLevel(1F) * 5F / 16F);
+            return 15F - (int) ((1F - cycle.bodyLight(PortDayCycle.nativeTicks(level)) * weather) * 11F);
+        });
+    }
+
     @Inject(method = "addDynamicLayers", at = @At("HEAD"), cancellable = true)
     private void rivencraft$dayCycle(Level level, CallbackInfoReturnable<EnvironmentAttributeSystem.Builder> cir) {
         var id = level.dimension().identifier();

ports/mc263/src/main/java/net/dnorberg/rivencraft/mixin/StaticSkyRendererMixin.java

@@ -26,6 +26,24 @@ public class StaticSkyRendererMixin {
     @Unique private int rivencraft$endTint = -1;
     @Unique private int rivencraft$orbitBearing = -1;
     @Unique private float rivencraft$sunSize = 1F;
+    @Unique private int rivencraft$celestialTint = -1;
+    @Unique private int rivencraft$bodyMode;
+    @Unique private java.util.List<StaticSkyState.Body> rivencraft$bodies = java.util.List.of();
+    @Unique private net.dnorberg.rivencraft.client.PortCelestialDiscs rivencraft$discs;
+    @Shadow @Final private net.minecraft.client.renderer.texture.TextureAtlas celestialsAtlas;
+    @Shadow private org.joml.Matrix4f applyCelestialBodyTransform(com.mojang.blaze3d.vertex.PoseStack pose,
+                                                                 float height, float size) { throw new AssertionError(); }
+    @Shadow private void renderSun(com.mojang.renderpearl.api.commands.RenderPass pass, float alpha,
+                                   com.mojang.blaze3d.vertex.PoseStack pose) { throw new AssertionError(); }
+    @Shadow private void renderMoon(com.mojang.renderpearl.api.commands.RenderPass pass,
+                                    net.minecraft.world.level.MoonPhase phase, float alpha,
+                                    com.mojang.blaze3d.vertex.PoseStack pose) { throw new AssertionError(); }
+    @Shadow private void renderStars(com.mojang.renderpearl.api.commands.RenderPass pass, float brightness,
+                                     com.mojang.blaze3d.vertex.PoseStack pose) { throw new AssertionError(); }
+    @Shadow private void renderSunMoonAndStars(com.mojang.renderpearl.api.commands.RenderPass pass,
+                                               com.mojang.blaze3d.vertex.PoseStack pose, float sunAngle,
+                                               float moonAngle, float starAngle, net.minecraft.world.level.MoonPhase phase,
+                                               float alpha, float stars) { throw new AssertionError(); }
 
     @Inject(method = "extractRenderState", at = @At("TAIL"))
     private void rivencraft$extract(ClientLevel level, float partialTicks, Camera camera,
@@ -36,11 +54,66 @@ public class StaticSkyRendererMixin {
         ((StaticSkyState) state).rivencraft$staticFrame(enabled ? level.getGameTime() / 2 : Long.MIN_VALUE);
         ((StaticSkyState) state).rivencraft$skyTint(net.dnorberg.rivencraft.age.PortAgeColors.forLevel(level).sky());
         var cycle = net.dnorberg.rivencraft.age.PortDayCycle.forLevel(level);
+        // 0=native Overworld/no authored overlay, 1=fog-only backdrop,
+        // 2=native End backdrop, 3=custom Static backdrop.
+        int overlay = !cycle.authored() || cycle.bodyMode() == net.dnorberg.rivencraft.age.PortDayCycle.NONE
+                || state.skybox == DimensionType.Skybox.OVERWORLD ? 0
+                : enabled ? 3 : state.skybox == DimensionType.Skybox.NONE ? 1 : 2;
+        ((StaticSkyState) state).rivencraft$bodyOverlay(overlay);
         ((StaticSkyState) state).rivencraft$orbitBearing(cycle.authored() ? cycle.bearing() : -1);
         ((StaticSkyState) state).rivencraft$sunSize(cycle.authored() ? cycle.sunSize() : 1F);
+        ((StaticSkyState) state).rivencraft$celestialTint(
+                net.dnorberg.rivencraft.age.PortAgeColors.forLevel(level).celestial());
+        ((StaticSkyState) state).rivencraft$bodyMode(cycle.authored() ? cycle.bodyMode() : 0);
+        // Root's authored Moon always samples the full-moon sprite. Preserve
+        // native calendar phases only for the native Normal Time pair.
+        if (cycle.singleBody() && cycle.bodyMode() == net.dnorberg.rivencraft.age.PortDayCycle.MOON)
+            state.moonPhase = net.minecraft.world.level.MoonPhase.FULL_MOON;
+        var authoredBodies = cycle.bodies();
+        if (authoredBodies.isEmpty() && overlay != 0) {
+            var bodies = new java.util.ArrayList<net.dnorberg.rivencraft.age.PortCelestialBody>();
+            int tint = net.dnorberg.rivencraft.age.PortAgeColors.forLevel(level).celestial();
+            if (cycle.bodyMode() != net.dnorberg.rivencraft.age.PortDayCycle.MOON)
+                bodies.add(net.dnorberg.rivencraft.age.PortCelestialBody.of(cycle, 1, tint, false));
+            if (cycle.bodyMode() != net.dnorberg.rivencraft.age.PortDayCycle.SUN)
+                bodies.add(net.dnorberg.rivencraft.age.PortCelestialBody.of(cycle, 2, tint, cycle.bodyMode() == 0));
+            authoredBodies = java.util.List.copyOf(bodies);
+        }
+        if (authoredBodies.isEmpty()) ((StaticSkyState) state).rivencraft$bodies(java.util.List.of());
+        else {
+            var clock = level.clockManager().getInstance(level.registryAccess().lookupOrThrow(
+                    net.minecraft.core.registries.Registries.WORLD_CLOCK).getOrThrow(net.minecraft.world.clock.WorldClocks.OVERWORLD));
+            double ticks = clock.totalTicks() + clock.partialTick();
+            var sources = authoredBodies;
+            var bodies = sources.stream().map(body -> {
+                float eclipse = body.eclipse(sources, ticks);
+                return new StaticSkyState.Body(body.kind(), body.angle(ticks), body.bearing(), body.size(),
+                        body.eclipseColor(eclipse), eclipse);
+            }).toList();
+            ((StaticSkyState) state).rivencraft$bodies(bodies);
+            float eclipse = 0;
+            for (var body : bodies) if (body.kind() == 1 && Math.cos(Math.toRadians(body.angle())) > 0)
+                eclipse = Math.max(eclipse, body.eclipse());
+            if (state.skybox == DimensionType.Skybox.OVERWORLD) {
+                state.skyColor = new org.joml.Vector3f(state.skyColor).mul(1F - 0.65F * eclipse);
+            } else if (eclipse > 0 && overlay >= 2) {
+                int tint = ((StaticSkyState) state).rivencraft$skyTint();
+                if (tint < 0) tint = enabled ? 0x929292 : 0xffffff;
+                ((StaticSkyState) state).rivencraft$skyTint(rivencraft$shade(tint, 1F - 0.65F * eclipse));
+            }
+        }
         // Only the extracted presentation uses END to schedule the sky pass. The actual
         // dimension has NONE, so it never acquires End flashes or End gameplay behavior.
-        if (enabled) state.skybox = DimensionType.Skybox.END;
+        if (enabled || overlay == 1) {
+            state.skybox = DimensionType.Skybox.END;
+            state.endFlashIntensity = 0;
+        }
+        if (overlay != 0) state.rainBrightness = 1F - level.getRainLevel(partialTicks);
+    }
+
+    @Unique private static int rivencraft$shade(int rgb, float shade) {
+        return Math.round((rgb >> 16 & 255) * shade) << 16
+                | Math.round((rgb >> 8 & 255) * shade) << 8 | Math.round((rgb & 255) * shade);
     }
 
     @Inject(method = "render", at = @At("HEAD"), cancellable = true)
@@ -49,9 +122,82 @@ public class StaticSkyRendererMixin {
         rivencraft$endTint = ((StaticSkyState) state).rivencraft$skyTint();
         rivencraft$orbitBearing = ((StaticSkyState) state).rivencraft$orbitBearing();
         rivencraft$sunSize = ((StaticSkyState) state).rivencraft$sunSize();
+        rivencraft$celestialTint = ((StaticSkyState) state).rivencraft$celestialTint();
+        rivencraft$bodyMode = ((StaticSkyState) state).rivencraft$bodyMode();
+        rivencraft$bodies = ((StaticSkyState) state).rivencraft$bodies();
+        if (((StaticSkyState) state).rivencraft$bodyOverlay() == 1) {
+            rivencraft$overlay(fog, state);
+            ci.cancel();
+            return;
+        }
         if (frame == Long.MIN_VALUE) return;
         if (rivencraft$staticSky == null) rivencraft$staticSky = new PortStaticSky();
         rivencraft$staticSky.render(renderTarget, fog, frame, rivencraft$endTint);
+        if (((StaticSkyState) state).rivencraft$bodyOverlay() == 3) rivencraft$overlay(fog, state);
+        ci.cancel();
+    }
+
+    @Inject(method = "render", at = @At("RETURN"))
+    private void rivencraft$afterBackground(GpuBufferSlice fog, SkyRenderState state, CallbackInfo ci) {
+        // RETURN includes the native End branch's early return, after its pass closes.
+        if (((StaticSkyState) state).rivencraft$bodyOverlay() == 2) rivencraft$overlay(fog, state);
+    }
+
+    @Unique private void rivencraft$overlay(GpuBufferSlice fog, SkyRenderState state) {
+        if (rivencraft$bodies.isEmpty()) return;
+        com.mojang.blaze3d.systems.RenderSystem.setShaderFog(fog);
+        try (var pass = com.mojang.blaze3d.systems.RenderSystem.getDevice().createCommandEncoder().createRenderPass(
+                () -> "Rivencraft celestial overlay", renderTarget.getColorTextureView(), java.util.Optional.empty(),
+                renderTarget.getDepthTextureView(), java.util.OptionalDouble.empty())) {
+            renderSunMoonAndStars(pass, new com.mojang.blaze3d.vertex.PoseStack(), 0, 0, 0,
+                    net.minecraft.world.level.MoonPhase.FULL_MOON, state.rainBrightness, 0);
+        }
+    }
+
+    @Inject(method = "renderSunMoonAndStars", at = @At("HEAD"), cancellable = true)
+    private void rivencraft$drawBodies(com.mojang.renderpearl.api.commands.RenderPass pass,
+                                       com.mojang.blaze3d.vertex.PoseStack pose, float sunAngle,
+                                       float moonAngle, float starAngle, net.minecraft.world.level.MoonPhase phase,
+                                       float alpha, float stars, CallbackInfo ci) {
+        if (rivencraft$bodies.isEmpty()) return;
+        int savedMode = rivencraft$bodyMode, savedTint = rivencraft$celestialTint;
+        float savedSize = rivencraft$sunSize;
+        try {
+            // Stars belong behind opaque discs, not on top of a dark eclipsing moon.
+            if (stars > 0) {
+                pose.pushPose();
+                try {
+                    pose.rotateDegrees(com.mojang.math.Axis.YP, -90);
+                    pose.rotate(com.mojang.math.Axis.XP, starAngle);
+                    renderStars(pass, stars, pose);
+                } finally { pose.popPose(); }
+            }
+            // Same ordering as 1.21.1: all suns, then all moons; each opaque
+            // central disc is drawn after its transparent glow.
+            for (int kind = 1; kind <= 2; kind++) for (var body : rivencraft$bodies) {
+                if (body.kind() != kind) continue;
+                rivencraft$bodyMode = kind;
+                rivencraft$celestialTint = body.color();
+                rivencraft$sunSize = body.size();
+                pose.pushPose();
+                try {
+                    pose.rotateDegrees(com.mojang.math.Axis.YP, body.bearing() < 0 ? -90 : body.bearing());
+                    pose.rotateDegrees(com.mojang.math.Axis.XP, body.angle());
+                    float glowAlpha = alpha * (kind == 1 ? 0.84F : 0.88F + 0.12F * body.eclipse());
+                    var bodyPhase = net.minecraft.world.level.MoonPhase.FULL_MOON;
+                    if (kind == 1) renderSun(pass, glowAlpha, pose); else renderMoon(pass, bodyPhase, glowAlpha, pose);
+                    if (rivencraft$discs == null) rivencraft$discs = new net.dnorberg.rivencraft.client.PortCelestialDiscs();
+                    // Both passes must use the same sprite. Native dark phase pixels
+                    // become black patches under ordinary alpha, unlike the old glow-only pass.
+                    var transform = applyCelestialBodyTransform(pose, 100F, (kind == 1 ? 30F : 20F) * body.size());
+                    rivencraft$discs.draw(pass, celestialsAtlas, kind == 2, bodyPhase, transform, body.color(), alpha);
+                } finally { pose.popPose(); }
+            }
+        } finally {
+            rivencraft$bodyMode = savedMode;
+            rivencraft$celestialTint = savedTint;
+            rivencraft$sunSize = savedSize;
+        }
         ci.cancel();
     }
 
@@ -68,10 +214,48 @@ public class StaticSkyRendererMixin {
         return nativeSize * rivencraft$sunSize;
     }
 
-    @Inject(method = "renderSunriseAndSunset", at = @At("HEAD"))
+    @ModifyArg(method = "renderMoon", at = @At(value = "INVOKE", target =
+            "Lnet/minecraft/client/renderer/SkyRenderer;applyCelestialBodyTransform(Lcom/mojang/blaze3d/vertex/PoseStack;FF)Lorg/joml/Matrix4f;"), index = 2)
+    private float rivencraft$scaleMoon(float nativeSize) {
+        return rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.MOON
+                ? nativeSize * rivencraft$sunSize : nativeSize;
+    }
+
+    @Inject(method = "renderSun", at = @At("HEAD"), cancellable = true)
+    private void rivencraft$hideSun(com.mojang.renderpearl.api.commands.RenderPass pass, float alpha,
+                                    com.mojang.blaze3d.vertex.PoseStack pose, CallbackInfo ci) {
+        if (rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.MOON
+                || rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.NONE) ci.cancel();
+    }
+
+    @Inject(method = "renderMoon", at = @At("HEAD"), cancellable = true)
+    private void rivencraft$hideMoon(com.mojang.renderpearl.api.commands.RenderPass pass,
+                                     net.minecraft.world.level.MoonPhase phase, float alpha,
+                                     com.mojang.blaze3d.vertex.PoseStack pose, CallbackInfo ci) {
+        if (rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.SUN
+                || rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.NONE) ci.cancel();
+    }
+
+    @ModifyArg(method = {"renderSun", "renderMoon"}, at = @At(value = "INVOKE", target =
+            "Lnet/minecraft/client/renderer/DynamicGpuData;writeTransform(Lorg/joml/Matrix4f;Lorg/joml/Vector4f;)Lcom/mojang/renderpearl/api/buffers/GpuBufferSlice;"), index = 1)
+    private org.joml.Vector4f rivencraft$tintCelestial(org.joml.Vector4f nativeColor) {
+        // Normal Time consumes one shared color group for its sun and moon in 1.21.1.
+        // Keep native alpha (including weather fading) and the sprite's transparent halo.
+        if (rivencraft$celestialTint < 0) return nativeColor;
+        var tint = net.dnorberg.rivencraft.age.PortAgeColors.vector(rivencraft$celestialTint);
+        return new org.joml.Vector4f(nativeColor.x * tint.x(), nativeColor.y * tint.y(),
+                nativeColor.z * tint.z(), nativeColor.w);
+    }
+
+    @Inject(method = "renderSunriseAndSunset", at = @At("HEAD"), cancellable = true)
     private void rivencraft$rotateHorizon(com.mojang.renderpearl.api.commands.RenderPass pass,
                                          com.mojang.blaze3d.vertex.PoseStack pose, float angle,
                                          org.joml.Vector4fc color, CallbackInfo ci) {
+        if (rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.MOON
+                || rivencraft$bodyMode == net.dnorberg.rivencraft.age.PortDayCycle.NONE) {
+            ci.cancel();
+            return;
+        }
         if (rivencraft$orbitBearing < 0) return;
         pose.pushPose();
         pose.rotateDegrees(com.mojang.math.Axis.YP, rivencraft$orbitBearing + 90);
@@ -81,7 +265,9 @@ public class StaticSkyRendererMixin {
     private void rivencraft$restoreHorizon(com.mojang.renderpearl.api.commands.RenderPass pass,
                                           com.mojang.blaze3d.vertex.PoseStack pose, float angle,
                                           org.joml.Vector4fc color, CallbackInfo ci) {
-        if (rivencraft$orbitBearing >= 0) pose.popPose();
+        if (rivencraft$bodyMode != net.dnorberg.rivencraft.age.PortDayCycle.MOON
+                && rivencraft$bodyMode != net.dnorberg.rivencraft.age.PortDayCycle.NONE
+                && rivencraft$orbitBearing >= 0) pose.popPose();
     }
 
     @Redirect(method = "renderEndSky", at = @At(value = "INVOKE", target =
@@ -94,6 +280,10 @@ public class StaticSkyRendererMixin {
 
     @Inject(method = "close", at = @At("HEAD"))
     private void rivencraft$close(CallbackInfo ci) {
+        if (rivencraft$discs != null) {
+            rivencraft$discs.close();
+            rivencraft$discs = null;
+        }
         if (rivencraft$staticSky != null) {
             rivencraft$staticSky.close();
             rivencraft$staticSky = null;

ports/mc263/src/main/java/net/dnorberg/rivencraft/mixin/StaticSkyStateMixin.java

@@ -14,6 +14,14 @@ public class StaticSkyStateMixin implements StaticSkyState {
     @Unique private int rivencraft$tint = -1;
     @Unique private int rivencraft$bearing = -1;
     @Unique private float rivencraft$sunSize = 1F;
+    @Unique private int rivencraft$celestialTint = -1;
+    @Unique private int rivencraft$bodyMode;
+    @Unique private int rivencraft$bodyOverlay;
+    public int rivencraft$bodyOverlay() { return rivencraft$bodyOverlay; }
+    public void rivencraft$bodyOverlay(int mode) { rivencraft$bodyOverlay = mode; }
+    @Unique private java.util.List<StaticSkyState.Body> rivencraft$bodies = java.util.List.of();
+    public java.util.List<StaticSkyState.Body> rivencraft$bodies() { return rivencraft$bodies; }
+    public void rivencraft$bodies(java.util.List<StaticSkyState.Body> bodies) { rivencraft$bodies = java.util.List.copyOf(bodies); }
     public long rivencraft$staticFrame() { return rivencraft$frame; }
     public void rivencraft$staticFrame(long frame) { rivencraft$frame = frame; }
     public int rivencraft$skyTint() { return rivencraft$tint; }
@@ -22,6 +30,10 @@ public class StaticSkyStateMixin implements StaticSkyState {
     public void rivencraft$orbitBearing(int bearing) { rivencraft$bearing = bearing; }
     public float rivencraft$sunSize() { return rivencraft$sunSize; }
     public void rivencraft$sunSize(float size) { rivencraft$sunSize = size; }
+    public int rivencraft$celestialTint() { return rivencraft$celestialTint; }
+    public void rivencraft$celestialTint(int color) { rivencraft$celestialTint = color; }
+    public int rivencraft$bodyMode() { return rivencraft$bodyMode; }
+    public void rivencraft$bodyMode(int mode) { rivencraft$bodyMode = mode; }
 
     @Inject(method = "reset", at = @At("TAIL"))
     private void rivencraft$reset(CallbackInfo ci) {
@@ -29,5 +41,9 @@ public class StaticSkyStateMixin implements StaticSkyState {
         rivencraft$tint = -1;
         rivencraft$bearing = -1;
         rivencraft$sunSize = 1F;
+        rivencraft$celestialTint = -1;
+        rivencraft$bodyMode = 0;
+        rivencraft$bodyOverlay = 0;
+        rivencraft$bodies = java.util.List.of();
     }
 }

ports/mc263/src/main/java/net/dnorberg/rivencraft/network/PortBookNetworking.java

@@ -108,9 +108,22 @@ public final class PortBookNetworking {
 
     public static Identifier createAge(ServerPlayer player, String title, List<Identifier> pages) {
         if (title == null || title.isBlank() || title.length() > MAX_BOOK_TITLE_LENGTH) return null;
+        long seed = player.getRandom().nextLong();
         net.dnorberg.rivencraft.age.PortBiomePlan biomePlan;
+        PortAgeTerrain terrain;
+        List<Identifier> generationPages;
         try {
-            biomePlan = PortAuthoredWriting.biomePlan(pages, player.registryAccess());
+            if (pages.isEmpty()) {
+                var random = PortRandomAgeSelection.select(player.level().getServer(), seed);
+                terrain = random.terrain();
+                biomePlan = random.biomes();
+                generationPages = pages;
+            } else {
+                var selected = net.dnorberg.rivencraft.writing.PortAuthoredTerrainSelection.select(player.level().getServer(), pages, seed);
+                terrain = selected.terrain();
+                biomePlan = selected.biomes();
+                generationPages = selected.generationPages();
+            }
         } catch (IllegalArgumentException exception) {
             player.sendOverlayMessage(Component.literal("Age writing unavailable: " + exception.getMessage()));
             return null;
@@ -127,24 +140,21 @@ public final class PortBookNetworking {
             id = Identifier.fromNamespaceAndPath(Rivencraft.MOD_ID, "age/" + name);
         }
         try {
-            long seed = player.getRandom().nextLong();
-            PortAgeTerrain terrain = PortAuthoredWriting.terrain(pages);
-            if (pages.isEmpty()) {
-                PortRandomAgeSelection.Selection random = PortRandomAgeSelection.select(server, seed);
-                terrain = random.terrain();
-                biomePlan = random.biomes();
-            }
             var environment = net.dnorberg.rivencraft.age.PortEnvironmentSelection.resolve(pages, seed, terrain);
-            RuntimeAgeBackend.create(server, id, seed, biomePlan, terrain,
-                    PortAuthoredWriting.rockPlan(pages, seed),
-                    PortAuthoredWriting.vegetationPlan(pages),
-                    PortAuthoredWriting.dungeonCount(pages),
-                    PortAuthoredWriting.lakePlan(pages, seed),
-                    PortAuthoredWriting.terrainFeaturePlan(pages, seed),
+            var randomFeatures = pages.isEmpty()
+                    ? net.dnorberg.rivencraft.age.PortRandomFeatureSelection.select(server, seed, terrain, biomePlan) : null;
+            var level = RuntimeAgeBackend.create(server, id, seed, biomePlan, terrain,
+                    randomFeatures == null ? PortAuthoredWriting.rockPlan(generationPages, seed) : randomFeatures.rocks(),
+                    PortAuthoredWriting.vegetationPlan(generationPages),
+                    randomFeatures == null ? PortAuthoredWriting.dungeonCount(generationPages) : randomFeatures.dungeons(),
+                    randomFeatures == null ? PortAuthoredWriting.lakePlan(generationPages, seed) : randomFeatures.lakes(),
+                    randomFeatures == null ? PortAuthoredWriting.terrainFeaturePlan(generationPages, seed) : randomFeatures.terrain(),
                     environment.weather(), environment.lighting(), environment.sky(),
-                    net.dnorberg.rivencraft.age.PortAgeColors.compile(pages, seed),
-                    net.dnorberg.rivencraft.age.PortDayCycle.compile(pages, seed,
+                    net.dnorberg.rivencraft.age.PortAgeColors.resolve(pages, seed),
+                    net.dnorberg.rivencraft.age.PortDayCycle.resolve(pages, seed,
                             net.dnorberg.rivencraft.age.PortDayCycle.nativeTicks(server.overworld())));
+            net.dnorberg.rivencraft.age.PortAcceleratedTicks.configure(level,
+                    net.dnorberg.rivencraft.age.PortAcceleratedTicks.pageCount(pages));
         } catch (IllegalArgumentException | IllegalStateException exception) {
             player.sendOverlayMessage(Component.literal("Age creation failed: " + exception.getMessage()));
             return null;

ports/mc263/src/main/java/net/dnorberg/rivencraft/writing/PortAuthoredTerrainSelection.java

@@ -0,0 +1,47 @@
+package net.dnorberg.rivencraft.writing;
+
+import java.util.ArrayList;
+import java.util.List;
+import net.dnorberg.rivencraft.age.PortAgeTerrain;
+import net.dnorberg.rivencraft.age.PortBiomePlan;
+import net.dnorberg.rivencraft.age.PortRandomAgeSelection;
+import net.minecraft.resources.Identifier;
+import net.minecraft.server.MinecraftServer;
+
+/** Root AgeRuntimeProfiles.selectForWriting, limited to currently supported port combinations. */
+public final class PortAuthoredTerrainSelection {
+    private PortAuthoredTerrainSelection() {}
+
+    public record Selection(PortAgeTerrain terrain, List<Identifier> generationPages, PortBiomePlan biomes) {
+        public Selection { generationPages = List.copyOf(generationPages); }
+    }
+
+    public static Selection select(MinecraftServer server, List<Identifier> pages, long seed) {
+        var explicit = PortAuthoredWriting.explicitTerrain(pages);
+        if (explicit != null) return compile(server, pages, seed, explicit);
+        var preferred = PortRandomAgeSelection.terrain(seed);
+        try {
+            return compile(server, pages, seed, preferred);
+        } catch (IllegalArgumentException ignored) {
+            // Match root's stable profile-ID fallback rather than rerolling the seed.
+        }
+        var compatible = new ArrayList<Selection>();
+        for (var terrain : PortRandomAgeSelection.terrains()) {
+            if (terrain == preferred) continue;
+            try { compatible.add(compile(server, pages, seed, terrain)); }
+            catch (IllegalArgumentException ignored) { }
+        }
+        if (compatible.isEmpty()) throw new IllegalArgumentException("No supported terrain can host this book's pages");
+        return compatible.get(Math.floorMod(Long.hashCode(seed), compatible.size()));
+    }
+
+    private static Selection compile(MinecraftServer server, List<Identifier> pages, long seed, PortAgeTerrain terrain) {
+        if (!PortAuthoredWriting.supportsOnTerrain(pages, terrain, seed))
+            throw new IllegalArgumentException("Unsupported pages for " + terrain + " terrain");
+        var resolved = PortAuthoredWriting.withTerrain(pages, terrain);
+        // Also preflight registry-backed biome restrictions, so an automatic Cave
+        // choice cannot turn supplied surface biome pages into an unusable book.
+        var biomes = PortAuthoredWriting.biomePlan(resolved, server, seed);
+        return new Selection(terrain, resolved, biomes);
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/writing/PortAuthoredWriting.java

@@ -57,6 +57,7 @@ public final class PortAuthoredWriting {
         if (entry == null) return false;
         if (net.dnorberg.rivencraft.age.PortAgeColors.isModifier(page)
                 || net.dnorberg.rivencraft.age.PortDayCycle.supports(page)) return true;
+        if (page.equals(net.dnorberg.rivencraft.age.PortAcceleratedTicks.PAGE)) return true;
         if (isTerrain(page) || controller(page) != null || PortWeatherMode.forPage(page) != null
                 || PortLighting.forPage(page) != null || PortSkyStyle.forPage(page) != null) return true;
         if (entry.category().equals("rivencraft:biome") && PortRegistryPages.biomeId(page) != null) return true;
@@ -72,6 +73,36 @@ public final class PortAuthoredWriting {
 
     /** A page never disappears into an Age unless this port can apply its effect. */
     public static boolean supports(List<Identifier> pages) {
+        if (pages.stream().noneMatch(PortAuthoredWriting::isTerrain))
+            return net.dnorberg.rivencraft.age.PortRandomAgeSelection.terrains().stream()
+                    .anyMatch(terrain -> supportsOnTerrain(pages, terrain, 0));
+        try {
+            return supportsExplicit(PortMaterialCompletion.complete(pages, 0));
+        } catch (IllegalArgumentException exception) { return false; }
+    }
+
+    static boolean supportsOnTerrain(List<Identifier> pages, PortAgeTerrain terrain, long seed) {
+        try {
+            return supportsExplicit(PortMaterialCompletion.complete(withTerrain(pages, terrain), seed));
+        } catch (IllegalArgumentException exception) { return false; }
+    }
+
+    static List<Identifier> withTerrain(List<Identifier> pages, PortAgeTerrain terrain) {
+        if (pages.stream().anyMatch(PortAuthoredWriting::isTerrain)) return List.copyOf(pages);
+        var resolved = new ArrayList<>(pages);
+        // Append internally so original material/color/controller indices stay stable.
+        resolved.add(Identifier.fromNamespaceAndPath(Rivencraft.MOD_ID,
+                "terrain/" + terrain.name().toLowerCase(java.util.Locale.ROOT)));
+        return List.copyOf(resolved);
+    }
+
+    static PortAgeTerrain explicitTerrain(List<Identifier> pages) {
+        return pages.stream().filter(PortAuthoredWriting::isTerrain).findFirst()
+                .map(page -> PortAgeTerrain.valueOf(page.getPath().substring(8).toUpperCase(java.util.Locale.ROOT)))
+                .orElse(null);
+    }
+
+    private static boolean supportsExplicit(List<Identifier> pages) {
         if (!net.dnorberg.rivencraft.age.PortAgeColors.validNumbers(pages)) return false;
         if (!net.dnorberg.rivencraft.age.PortDayCycle.validWriting(pages)) return false;
         boolean terrain = false;
@@ -97,7 +128,9 @@ public final class PortAuthoredWriting {
                     || pendingMaterial.equals("rivencraft:fluid") && PortLakePlan.isLake(page))) return false;
             if (net.dnorberg.rivencraft.age.PortAgeColors.isModifier(page)
                     || net.dnorberg.rivencraft.age.PortDayCycle.supports(page)) {
-                // Shared color groups can precede a sky/ambient target or tint the sky at the end.
+                // Shared colors target Sky, Ambient Light Color or Normal Time; trailing colors tint the sky.
+            } else if (page.equals(net.dnorberg.rivencraft.age.PortAcceleratedTicks.PAGE)) {
+                // Every Accelerated page adds random-tick attempts; it is not a controller.
             } else if (isTerrain(page) && !terrain) {
                 terrain = true;
             } else if (PortSkyStyle.forPage(page) != null && sky++ == 0) {
@@ -107,7 +140,7 @@ public final class PortAuthoredWriting {
             } else if (PortWeatherMode.forPage(page) != null && weather++ == 0) {
                 // A single independent weather policy for this Age.
             } else if (controller(page) != null && controllers++ == 0) {
-                // An explicit controller needs an authored pool.
+                // Missing biome slots are seed-completed when the Age is created.
             } else if (isBlockPage(page) && pendingMaterial == null
                     && PortSymbolPages.find(page) != null
                     && (PortSymbolPages.find(page).category().equals("rivencraft:block")
@@ -152,7 +185,8 @@ public final class PortAuthoredWriting {
         }
         if (pendingMaterial != null || (rocks > 0 || pages.stream().anyMatch(PortVegetationPlan::requiresSurface))
                 && (pages.contains(CAVE_TERRAIN) || pages.contains(VOID_TERRAIN))) return false;
-        if ((dungeons > 0 || lakes > 0) && (pages.contains(FLAT_TERRAIN) || pages.contains(VOID_TERRAIN)
+        if (dungeons > 0 && (pages.contains(FLAT_TERRAIN) || pages.contains(VOID_TERRAIN))) return false;
+        if (lakes > 0 && (pages.contains(FLAT_TERRAIN) || pages.contains(VOID_TERRAIN)
                 || pages.contains(CAVE_TERRAIN))) return false;
         if (denseOres > 0 && (pages.contains(FLAT_TERRAIN) || pages.contains(VOID_TERRAIN))) return false;
         if (!carvers.isEmpty() && (pages.contains(FLAT_TERRAIN) || pages.contains(VOID_TERRAIN))) return false;
@@ -169,8 +203,8 @@ public final class PortAuthoredWriting {
                     .filter(value -> value != null).findFirst().orElseThrow();
             boolean valid = switch (distribution) {
                 case NATIVE -> biomes == 0;
-                case SINGLE -> biomes == 1;
-                default -> biomes >= 2;
+                case SINGLE -> biomes <= 1;
+                default -> true;
             };
             return valid;
         }
@@ -214,13 +248,14 @@ public final class PortAuthoredWriting {
     }
 
     public static PortRockPlan rockPlan(List<Identifier> pages, long seed) {
-        if (!supports(pages)) throw new IllegalArgumentException("Unsupported authored Age pages");
+        pages = completedMaterials(pages, seed);
         List<Identifier> materials = solidMaterials(pages, seed, ROCKS);
         return materials.isEmpty() ? null : new PortRockPlan(materials);
     }
 
     public static PortTerrainFeaturePlan terrainFeaturePlan(List<Identifier> pages, long seed) {
-        if (!supports(pages)) throw new IllegalArgumentException("Unsupported authored Age pages");
+        pages = completedMaterials(pages, seed);
+        final List<Identifier> completed = pages;
         Map<Identifier, List<Identifier>> materials = new HashMap<>();
         Map<Identifier, Integer> occurrences = new HashMap<>();
         List<PortTerrainFeaturePlan.Choice> choices = new ArrayList<>();
@@ -230,7 +265,7 @@ public final class PortAuthoredWriting {
                 choices.add(new PortTerrainFeaturePlan.Choice(page, PortTerrainFeaturePlan.CRYSTAL_MATERIAL));
                 continue;
             }
-            List<Identifier> selected = materials.computeIfAbsent(page, feature -> solidMaterials(pages, seed, feature));
+            List<Identifier> selected = materials.computeIfAbsent(page, feature -> solidMaterials(completed, seed, feature));
             int occurrence = occurrences.merge(page, 1, Integer::sum) - 1;
             choices.add(new PortTerrainFeaturePlan.Choice(page, selected.get(occurrence)));
         }
@@ -262,7 +297,7 @@ public final class PortAuthoredWriting {
     }
 
     public static PortLakePlan lakePlan(List<Identifier> pages, long seed) {
-        if (!supports(pages)) throw new IllegalArgumentException("Unsupported authored Age pages");
+        pages = completedMaterials(pages, seed);
         if (pages.stream().noneMatch(PortLakePlan::isLake)) return null;
         List<Identifier> fluidPool = PortRegistryPages.fluidMaterialIds();
         if (fluidPool.isEmpty()) throw new IllegalStateException("No source-fluid materials are registered");
@@ -288,6 +323,12 @@ public final class PortAuthoredWriting {
         return new PortLakePlan(choices);
     }
 
+    private static List<Identifier> completedMaterials(List<Identifier> pages, long seed) {
+        var completed = PortMaterialCompletion.complete(pages, seed);
+        if (!supportsExplicit(completed)) throw new IllegalArgumentException("Unsupported authored Age pages");
+        return completed;
+    }
+
     public static PortVegetationPlan vegetationPlan(List<Identifier> pages) {
         if (!supports(pages)) throw new IllegalArgumentException("Unsupported authored Age pages");
         List<Identifier> vegetation = pages.stream().filter(PortVegetationPlan::isVegetation).toList();
@@ -307,6 +348,18 @@ public final class PortAuthoredWriting {
 
     /** Resolves all authored biomes from the active registry before creating a level. */
     public static PortBiomePlan biomePlan(List<Identifier> pages, HolderLookup.Provider registries) {
+        return biomePlan(pages, registries, 0, null, null);
+    }
+
+    /** Creation-only completion; the saved plan never rerolls on load or reseed. */
+    public static PortBiomePlan biomePlan(List<Identifier> pages, net.minecraft.server.MinecraftServer server, long seed) {
+        return biomePlan(pages, server.registryAccess(), seed,
+                net.dnorberg.rivencraft.age.PortRandomAgeSelection.eligibleBiomes(server, terrain(pages)),
+                net.dnorberg.rivencraft.age.PortRandomAgeSelection.distribution(seed));
+    }
+
+    private static PortBiomePlan biomePlan(List<Identifier> pages, HolderLookup.Provider registries,
+                                          long seed, List<Identifier> available, PortBiomePlan.Distribution fallback) {
         if (!supports(pages)) throw new IllegalArgumentException(
                 "Unsupported terrain or biome-page combination in this port slice");
         List<Identifier> biomes = new ArrayList<>();
@@ -339,8 +392,44 @@ public final class PortAuthoredWriting {
             throw new IllegalArgumentException("Vegetation pages need at least one surface Overworld biome");
         if (pages.contains(PortTerrainFeaturePlan.DENSE_ORES) && !biomes.isEmpty() && !hasOreBiome)
             throw new IllegalArgumentException("Dense Ores needs at least one biome with registered ore placements");
-        if (distribution == PortBiomePlan.Distribution.NATIVE)
-            return new PortBiomePlan(distribution, List.of());
+        if (distribution == null && fallback != null) {
+            distribution = fallback;
+            // Root's authored-pool fallback never discards supplied biome pages.
+            if (pages.contains(VOID_TERRAIN) && biomes.isEmpty()) distribution = PortBiomePlan.Distribution.SINGLE;
+            if (!biomes.isEmpty() && (pages.contains(VOID_TERRAIN)
+                    || distribution == PortBiomePlan.Distribution.NATIVE
+                    || distribution == PortBiomePlan.Distribution.SINGLE && biomes.size() > 1))
+                distribution = biomes.size() == 1 ? PortBiomePlan.Distribution.SINGLE : biomes.size() == 2
+                        ? PortBiomePlan.Distribution.TILED : PortBiomePlan.Distribution.MEDIUM;
+        }
+        if (distribution == PortBiomePlan.Distribution.NATIVE) {
+            var nativePool = caveTerrain
+                    ? (available != null ? available : net.dnorberg.rivencraft.age.PortRandomAgeSelection.caveBiomes(registries))
+                    : List.<Identifier>of();
+            return new PortBiomePlan(distribution, nativePool);
+        }
+        if (distribution != null && available != null) {
+            int minimum = distribution == PortBiomePlan.Distribution.SINGLE ? 1 : 2;
+            int target = minimum;
+            if (biomes.isEmpty() && distribution != PortBiomePlan.Distribution.SINGLE) {
+                var random = new Random(seed ^ 0x42494F4D45434F55L);
+                while (target < available.size() && random.nextInt(3) != 0) target++;
+            }
+            var distinct = new java.util.HashSet<>(biomes);
+            PortStructureBiomeCompletion.complete(pages, registries, available, !biomes.isEmpty(),
+                    distribution, biomes, distinct, seed);
+            target = Math.max(target, distinct.size());
+            // Void may retain authored weather/season biomes, but must not gain
+            // an unrequested The Void biome just to fill a multi-biome controller.
+            var filler = new ArrayList<>(pages.contains(VOID_TERRAIN) && !biomes.isEmpty() ? List.<Identifier>of() : available);
+            Collections.shuffle(filler, new Random(seed ^ 0x42494F4D45504F4FL));
+            for (Identifier biome : filler) {
+                if (distinct.size() >= target) break;
+                if (distinct.add(biome)) biomes.add(biome);
+            }
+            if (distinct.size() < minimum) throw new IllegalArgumentException(
+                    distribution + " requires " + minimum + " distinct biomes; supply more biome pages for this terrain");
+        }
         if (biomes.isEmpty()) return null;
         if (distribution == null) distribution = biomes.size() == 1
                 ? PortBiomePlan.Distribution.SINGLE : biomes.size() == 2

ports/mc263/src/main/java/net/dnorberg/rivencraft/writing/PortMaterialCompletion.java

@@ -0,0 +1,68 @@
+package net.dnorberg.rivencraft.writing;
+
+import java.util.ArrayList;
+import java.util.List;
+import net.dnorberg.rivencraft.age.PortCarverPages;
+import net.dnorberg.rivencraft.age.PortLakePlan;
+import net.dnorberg.rivencraft.age.PortStructurePages;
+import net.dnorberg.rivencraft.age.PortTerrainFeaturePlan;
+import net.dnorberg.rivencraft.age.PortVegetationPlan;
+import net.minecraft.resources.Identifier;
+
+/** Creation-time implied features, adapted from 1.21.1 AgeFeatureSelection. */
+public final class PortMaterialCompletion {
+    private PortMaterialCompletion() {}
+
+    public static List<Identifier> complete(List<Identifier> pages, long seed) {
+        var result = new ArrayList<Identifier>();
+        for (int index = 0; index < pages.size(); index++) {
+            Identifier page = pages.get(index);
+            result.add(page);
+            var entry = PortSymbolPages.find(page);
+            if (entry == null || !(entry.category().equals("rivencraft:block")
+                    || entry.category().equals("rivencraft:fluid"))) continue;
+            if (index + 1 < pages.size() && isFeature(pages.get(index + 1))) continue;
+            Identifier material = PortRegistryPages.blockId(page);
+            var candidates = candidates(pages, entry.category().equals("rivencraft:fluid"));
+            if (candidates.isEmpty()) throw new IllegalArgumentException(
+                    "No compatible feature for material " + material + " on this terrain");
+            long mixed = mix(seed ^ (long) material.hashCode() * 0x9E3779B97F4A7C15L ^ index);
+            result.add(candidates.get(Math.floorMod(mixed, candidates.size())));
+        }
+        return List.copyOf(result);
+    }
+
+    private static List<Identifier> candidates(List<Identifier> pages, boolean fluid) {
+        boolean cave = pages.contains(id("terrain/cave"));
+        boolean empty = pages.contains(id("terrain/void"));
+        boolean flat = pages.contains(id("terrain/flat"));
+        if (fluid) return cave || empty || flat ? List.of()
+                : List.of(id("feature/surface_lakes"), id("feature/deep_lakes"), id("feature/lava_lakes"));
+        var choices = new ArrayList<Identifier>();
+        if (!cave && !empty && !flat) choices.add(id("feature/rocks"));
+        if (!cave) choices.add(PortTerrainFeaturePlan.FLOATING_ISLANDS);
+        choices.add(PortTerrainFeaturePlan.TENDRILS);
+        choices.add(PortTerrainFeaturePlan.SPHERES);
+        if (!cave && !empty) {
+            choices.add(PortTerrainFeaturePlan.SPIKES);
+            choices.add(PortTerrainFeaturePlan.OBELISKS);
+        }
+        return choices;
+    }
+
+    private static boolean isFeature(Identifier page) {
+        return PortTerrainFeaturePlan.isSupported(page) || PortLakePlan.isLake(page)
+                || PortVegetationPlan.isVegetation(page) || PortStructurePages.supports(page)
+                || PortCarverPages.supports(page) || page.equals(id("feature/rocks"))
+                || page.equals(id("feature/dungeons")) || page.equals(PortTerrainFeaturePlan.SKYLANDS)
+                || page.equals(PortTerrainFeaturePlan.DENSE_ORES) || page.equals(PortTerrainFeaturePlan.STAR_FISSURES);
+    }
+
+    private static Identifier id(String path) { return Identifier.fromNamespaceAndPath("rivencraft", path); }
+
+    private static long mix(long value) {
+        value = (value ^ value >>> 30) * 0xBF58476D1CE4E5B9L;
+        value = (value ^ value >>> 27) * 0x94D049BB133111EBL;
+        return value ^ value >>> 31;
+    }
+}

ports/mc263/src/main/java/net/dnorberg/rivencraft/writing/PortStructureBiomeCompletion.java

@@ -0,0 +1,54 @@
+package net.dnorberg.rivencraft.writing;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+import net.dnorberg.rivencraft.age.PortBiomePlan;
+import net.dnorberg.rivencraft.age.PortStructurePages;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.resources.Identifier;
+
+/** Root AgeBiomeSelection.completeStructureBiomes, before ordinary minimum filling. */
+final class PortStructureBiomeCompletion {
+    private PortStructureBiomeCompletion() {}
+
+    static void complete(List<Identifier> pages, HolderLookup.Provider registries, List<Identifier> available,
+                         boolean hasAuthoredBiomes, PortBiomePlan.Distribution distribution,
+                         List<Identifier> selected, Set<Identifier> distinct, long seed) {
+        var requirements = pages.stream().filter(PortStructurePages::supports).distinct()
+                .map(page -> PortStructurePages.compatibleBiomes(page, registries))
+                .filter(requirement -> !requirement.isEmpty()).toList();
+        if (requirements.isEmpty()) return;
+        if (distribution == PortBiomePlan.Distribution.SINGLE) {
+            if (hasAuthoredBiomes) return;
+            var candidates = available.stream()
+                    .filter(candidate -> requirements.stream().allMatch(requirement -> requirement.contains(candidate)))
+                    .toList();
+            if (candidates.isEmpty()) return;
+            Identifier biome = choose(candidates, seed, 0x5354525543544249L);
+            selected.clear();
+            distinct.clear();
+            selected.add(biome);
+            distinct.add(biome);
+            return;
+        }
+        for (int index = 0; index < requirements.size(); index++) {
+            var requirement = requirements.get(index);
+            if (selected.stream().anyMatch(requirement::contains)) continue;
+            var candidates = available.stream().filter(requirement::contains)
+                    .filter(candidate -> !distinct.contains(candidate)).toList();
+            if (candidates.isEmpty()) continue;
+            Identifier biome = choose(candidates, seed, 0x5354525543544249L + index);
+            selected.add(biome);
+            distinct.add(biome);
+        }
+    }
+
+    private static Identifier choose(List<Identifier> candidates, long seed, long salt) {
+        var shuffled = new ArrayList<>(candidates);
+        Collections.shuffle(shuffled, new Random(seed ^ salt));
+        return shuffled.getFirst();
+    }
+}