Add optional authored Ruins structures to Ages (#91)

README.md

@@ -118,6 +118,28 @@ book or page is placed on it; this in-world interaction has no JEI guide.
 With Create installed, Crystal Blocks and Book Receptacles have an optional Ponder scene
 showing crystal-frame construction, book activation, and a parrot crossing the portal. Use the Ponder shortcut
 while hovering either item; Rivencraft does not require Create to run.
+Crystal frames may stand vertically or lie flat: a 3×3 Crystal Block ring with
+an empty center forms a horizontal portal when a Book Receptacle is attached to
+the top or underside of one of its blocks. Insert a bound Linking or Descriptive
+Book to activate it; the book remains visible on the receptacle. A Linking Book aimed at its
+own dimension still opens a visual portal, but travel requires Intra Linking.
+
+Sky writing has shared Red, Green, Blue, White, and Black pages plus 25 D'ni
+number pages (0–24). Put colors before a Sky, Sun, or Moon page to color that
+target; trailing colors tint the sky. A number immediately before a color sets
+its strength to number × 10. Without a number, a color gets a seeded random
+strength from 0–24. RGB contributions add in any order, White brightens all
+channels, Black subtracts from all channels, and omitted channels remain zero.
+The resulting sky color also tints book previews and fallback portal surfaces.
+An Age may have no suns or moons at all; Static Sky animates with fine-grained
+television-like noise. Sun and Moon pages add
+independent bodies; preceding color, size, angle, period, phase, and direction
+pages configure the next body. The third and each subsequent sun add increasing
+instability. Overlapping moon and sun discs produce an eclipse: the moon darkens,
+the sun's color brightens at close alignment, and world and sky lighting dim.
+Newly generated page-free Ages also choose a deterministic sky,
+color, and celestial arrangement from their Age seed; older saved Ages retain
+their previous sky.
 
 Craft a Book Binder from three iron ingots and five planks. Put leather or an
 empty Notebook in the left cover slot. Enter a title, then place a Link Panel
@@ -211,6 +233,9 @@ Data-pack runtime profiles are documented in
 - NeoForge 21.1.264 or newer in the 21.1 line
 - Dynamic Dimensions AR Edition 0.9.1 and Bad Packets 0.8.2 (client and server)
 
+Ruins is optional. When installed, its configured structures have individual
+authorable pages; see [Ruins compatibility](docs/RUINS_COMPATIBILITY.md).
+
 Create is optional. When installed, Rivencraft uses its Ponder renderer for
 book previews when Immersive Portals is absent. Immersive Portals is also
 optional and takes priority in the default `AUTO` mode, providing a live

build.gradle

@@ -245,6 +245,11 @@ dependencies {
     // Keep them on the compile classpath without forcing either mod at runtime.
     compileOnly "net.createmod.ponder:ponder-neoforge:${ponder_version}+mc${minecraft_version}"
     compileOnly "maven.modrinth:immersive-portals-neoforge:${immersive_portals_version}"
+    // Ruins is optional; its pre-spawn event is only registered when Ruins is loaded.
+    compileOnly 'curse.maven:ruins-227873:6391825'
+    if (providers.gradleProperty('withRuins').map { it.toBoolean() }.orElse(false).get()) {
+        localRuntime 'curse.maven:ruins-227873:6391825'
+    }
     // TerraBlender's region API is only used by the guarded compat adapter.
     compileOnly "com.github.glitchfiend:TerraBlender-neoforge:${minecraft_version}-${terrablender_version}"
     if (providers.gradleProperty('withTerraBlender').map { it.toBoolean() }.orElse(false).get()) {

docs/RUINS_COMPATIBILITY.md

@@ -0,0 +1,66 @@
+# Optional Ruins template pages (issue #91)
+
+Rivencraft supports Ruins 1.21.1.2NF as an optional mod. When it is installed,
+every `.tml` template in Ruins' active `config/ruins_config/<generic-or-biome>/`
+folders receives a separate Ruins page in Rivencraft's creative and JEI page
+feeds. New templates added to Ruins' config appear after a restart; removing a
+template makes its page unavailable to new books. With Ruins absent, no Ruins
+pages or structure integration are active.
+
+An authored Age with Ruins pages is admitted through Ruins' dimension gate.
+Rivencraft also admits the authored templates through their individual
+`dimensionsToSpawnIn` gates, which usually list only `overworld` and would
+otherwise prevent them from loading in an Age. Ruins still owns chunk
+inspection, spawn chance, surface validation, biome pools, and spacing.
+Rivencraft filters Ruins' weighted
+template choice to the exact pages in that Age and vetoes an unauthorized
+template in Ruins' pre-spawn event. A page therefore selects *which* template
+may appear; it does not guarantee a structure in every chunk. Manual
+`/testruin` placements are unaffected.
+
+Repeating a template page multiplies that template's Ruins selection weight by
+its page count and adds one spawn attempt per chunk for each duplicate page.
+The extra attempts are capped at 32 per chunk (or Ruins' configured count if
+higher). Distinct template pages do not add attempts, and Ruins' spacing and
+surface checks still apply. As with Rivencraft's standard
+structure pages, the first three copies of each template are instability-free;
+each additional copy adds 100 instability. Ruins retains its own biome and
+surface checks, so the standard structure forced-biome penalty does not apply.
+
+Ruins' event identifies a template only by its filename. If two active folders
+contain the same `.tml` basename, Rivencraft cannot distinguish them and
+disables all Ruins pages for that configuration. Give each template a unique
+filename to restore support. Ruins must also be able to parse the template and
+find a suitable surface in the selected biome; a page cannot repair an invalid
+or biome-incompatible template.
+
+The adapter and dimension/selection mixin are version-sensitive to Ruins
+1.21.1.2NF. The published Rivencraft jar does not include Ruins. To include it
+in a development run, use `-PwithRuins=true`.
+
+## Manual check
+
+1. Start a client with Ruins 1.21.1.2NF and Rivencraft 0.6.9.3. Confirm the
+   Ruins Pages tab contains one page per configured `.tml` file, and search a
+   distinctive template name in JEI.
+2. Bind a new Descriptive Book with a Link Panel, Standard Terrain, a suitable
+   surface biome, and one Ruins page (for example ZombieHut). Enter the Age and
+   explore *unvisited* chunks. Ruins marks inspected chunks and will not retry
+   chunks explored under the earlier broken build. Only the selected Ruins
+   template should appear. Ruins'
+   own chance and distance settings still determine how far exploration takes.
+3. For duplicate weighting, bind an Age with one copy of one template page and
+   three copies of a second template page valid in the same biome. Across enough
+   new candidate chunks, the second should be selected more often relative to
+   the first, and there should be two additional spawn attempts per inspected
+   chunk. Four copies of one template should add 100 instability, visible
+   through the OP Age instability diagnostic, while three copies add none.
+4. Make another Age without a Ruins page and confirm Ruins structures do not
+   appear there. Restart the game and confirm the authored Age keeps its page
+   selection. Then remove Ruins and confirm Rivencraft starts normally without
+   a Ruins tab.
+
+The Ruins-enabled GameTest server passed all 90 required tests and loaded the
+template-dimension and attempt mixins. Its test world was removed afterward.
+Use the client check above to verify actual Ruins generation and the increased
+attempt rate.

gradle.properties

@@ -36,7 +36,7 @@ mod_name=Rivencraft
 # The license of the mod. Review your options at https://choosealicense.com/. All Rights Reserved is the default.
 mod_license=LGPL-3.0-or-later
 # The mod version. Rivencraft uses the x.y.z.b policy documented in README.md.
-mod_version=0.6.7.3
+mod_version=0.6.9.3
 immersive_portals_version=6.0.7
 terrablender_version=4.1.0.8
 serene_seasons_version_id=pHEgQQUE

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

@@ -20,6 +20,7 @@ import net.dnorberg.rivencraft.network.ModNetworking;
 import net.dnorberg.rivencraft.config.RivencraftConfig;
 import net.dnorberg.rivencraft.config.RivencraftClientConfig;
 import net.dnorberg.rivencraft.compat.SereneSeasonsCompatibility;
+import net.dnorberg.rivencraft.compat.RuinsCompatibility;
 import net.dnorberg.rivencraft.book.AgeDimensionService;
 import net.dnorberg.rivencraft.book.AgeWeatherService;
 import net.dnorberg.rivencraft.book.AgeInstabilityRuntime;
@@ -43,6 +44,7 @@ public final class Rivencraft {
 
     public Rivencraft(IEventBus modEventBus, ModContainer modContainer) {
         AgeDimensionService.register();
+        RuinsCompatibility.register();
         AgeStatusEffectProviders.register();
         AgeDecayProviders.register();
         AgeHazardProviders.register();
@@ -82,6 +84,8 @@ public final class Rivencraft {
         NeoForge.EVENT_BUS.addListener(AgeInstabilityRuntime::onServerStopping);
         NeoForge.EVENT_BUS.addListener(AgeEnvironmentalProviders::onServerStopping);
         NeoForge.EVENT_BUS.addListener(AgeStatusEffectProviders::onServerStopping);
+        NeoForge.EVENT_BUS.addListener((net.neoforged.neoforge.event.server.ServerStoppingEvent event) ->
+                RuinsCompatibility.onServerStopping());
         NeoForge.EVENT_BUS.addListener(RivencraftCommands::register);
         NeoForge.EVENT_BUS.addListener(LibraryLocateService::onServerTickPost);
         NeoForge.EVENT_BUS.addListener(LibraryLocateService::onServerStopping);

src/main/java/net/dnorberg/rivencraft/block/BookReceptacleBlock.java

@@ -36,6 +36,7 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.block.state.StateDefinition;
 import net.minecraft.world.level.block.state.properties.BlockStateProperties;
 import net.minecraft.world.level.block.state.properties.DirectionProperty;
+import net.minecraft.world.level.block.state.properties.BooleanProperty;
 import net.minecraft.world.phys.BlockHitResult;
 import net.minecraft.world.phys.shapes.CollisionContext;
 import net.minecraft.world.phys.shapes.VoxelShape;
@@ -44,10 +45,11 @@ import net.minecraft.world.phys.shapes.VoxelShape;
 public final class BookReceptacleBlock extends BaseEntityBlock {
     public static final MapCodec<BookReceptacleBlock> CODEC = simpleCodec(BookReceptacleBlock::new);
     public static final DirectionProperty FACING = BlockStateProperties.FACING;
+    public static final BooleanProperty HAS_BOOK = BlockStateProperties.HAS_BOOK;
 
     public BookReceptacleBlock(Properties properties) {
         super(properties);
-        registerDefaultState(stateDefinition.any().setValue(FACING, Direction.NORTH));
+        registerDefaultState(stateDefinition.any().setValue(FACING, Direction.NORTH).setValue(HAS_BOOK, false));
     }
 
     @Override protected MapCodec<? extends BaseEntityBlock> codec() { return CODEC; }
@@ -64,7 +66,7 @@ public final class BookReceptacleBlock extends BaseEntityBlock {
         };
     }
     @Override protected void createBlockStateDefinition(StateDefinition.Builder<Block, BlockState> builder) {
-        builder.add(FACING);
+        builder.add(FACING, HAS_BOOK);
     }
     @Override public BlockEntity newBlockEntity(BlockPos pos, BlockState state) {
         return new BookReceptacleBlockEntity(pos, state);
@@ -77,7 +79,7 @@ public final class BookReceptacleBlock extends BaseEntityBlock {
     }
     @Override public BlockState getStateForPlacement(BlockPlaceContext context) {
         Direction face = context.getClickedFace();
-        if (face == Direction.DOWN || !context.getLevel().getBlockState(
+        if (!context.getLevel().getBlockState(
                 context.getClickedPos().relative(face.getOpposite())).is(ModBlocks.CRYSTAL_BLOCK.get())) return null;
         return defaultBlockState().setValue(FACING, face);
     }
@@ -153,7 +155,7 @@ public final class BookReceptacleBlock extends BaseEntityBlock {
         if (!state.is(replacement.getBlock()) && level instanceof ServerLevel server) {
             CrystalPortalNetwork.shutdown(server, pos);
             if (level.getBlockEntity(pos) instanceof BookReceptacleBlockEntity holder) {
-                ItemStack book = holder.takeBook();
+                ItemStack book = holder.takeBookOnBreak();
                 if (!book.isEmpty()) level.addFreshEntity(new ItemEntity(level, pos.getX()+0.5, pos.getY()+0.5,
                         pos.getZ()+0.5, book));
             }

src/main/java/net/dnorberg/rivencraft/block/entity/BookReceptacleBlockEntity.java

@@ -1,7 +1,10 @@
 package net.dnorberg.rivencraft.block.entity;
 
 import net.dnorberg.rivencraft.book.LinkTarget;
+import net.dnorberg.rivencraft.book.AgeEnvironmentCompiler;
+import net.dnorberg.rivencraft.block.BookReceptacleBlock;
 import net.dnorberg.rivencraft.registry.ModBlockEntities;
+import net.dnorberg.rivencraft.registry.ModBlocks;
 import net.dnorberg.rivencraft.portal.CrystalPortalNetwork;
 import net.minecraft.nbt.NbtOps;
 import net.minecraft.core.BlockPos;
@@ -20,8 +23,10 @@ import net.neoforged.fml.ModList;
 public final class BookReceptacleBlockEntity extends BlockEntity {
     private static final String BOOK_TAG = "Book";
     private static final String DESTINATION_TAG = "Destination";
+    private static final String SKY_COLOR_TAG = "SkyColor";
     private ItemStack book = ItemStack.EMPTY;
     private LinkTarget destination;
+    private int skyColor = 0xFFFFFF;
     private boolean restoreView = true;
 
     public BookReceptacleBlockEntity(BlockPos pos, BlockState state) {
@@ -30,6 +35,7 @@ public final class BookReceptacleBlockEntity extends BlockEntity {
 
     public ItemStack getBook() { return book; }
     public LinkTarget destination() { return destination; }
+    public int skyColor() { return skyColor; }
 
     public void setBook(ItemStack stack) {
         book = stack.copyWithCount(1);
@@ -38,21 +44,46 @@ public final class BookReceptacleBlockEntity extends BlockEntity {
 
     public void setDestination(LinkTarget target) {
         destination = target;
+        skyColor = 0xFFFFFF;
+        if (target != null && level instanceof ServerLevel server) {
+            ServerLevel targetLevel = server.getServer().getLevel(target.location().dimension());
+            if (targetLevel != null) skyColor = AgeEnvironmentCompiler.previewSkyColor(
+                    targetLevel, target.location().pos()) & 0xFFFFFF;
+        }
         sync();
     }
 
     public ItemStack takeBook() {
+        return removeBook(true);
+    }
+
+    /** The block is already being replaced, so do not write its state back into the world. */
+    public ItemStack takeBookOnBreak() {
+        return removeBook(false);
+    }
+
+    private ItemStack removeBook(boolean notify) {
         ItemStack result = book;
         book = ItemStack.EMPTY;
         destination = null;
-        sync();
+        skyColor = 0xFFFFFF;
+        if (notify) sync();
+        else setChanged();
         return result;
     }
 
     private void sync() {
         setChanged();
-        if (level != null && !level.isClientSide)
-            level.sendBlockUpdated(worldPosition, getBlockState(), getBlockState(), 2);
+        if (level instanceof ServerLevel server) {
+            BlockState state = server.getBlockState(worldPosition);
+            if (!state.is(ModBlocks.BOOK_RECEPTACLE.get())) return;
+            boolean hasBook = !book.isEmpty();
+            if (state.getValue(BookReceptacleBlock.HAS_BOOK) != hasBook) {
+                state = state.setValue(BookReceptacleBlock.HAS_BOOK, hasBook);
+                server.setBlock(worldPosition, state, 2);
+            }
+            server.sendBlockUpdated(worldPosition, state, state, 2);
+        }
     }
 
     @Override
@@ -63,6 +94,7 @@ public final class BookReceptacleBlockEntity extends BlockEntity {
                 : ItemStack.EMPTY;
         destination = tag.contains(DESTINATION_TAG)
                 ? LinkTarget.CODEC.parse(NbtOps.INSTANCE, tag.get(DESTINATION_TAG)).result().orElse(null) : null;
+        skyColor = tag.contains(SKY_COLOR_TAG) ? tag.getInt(SKY_COLOR_TAG) & 0xFFFFFF : 0xFFFFFF;
         restoreView = true;
     }
 
@@ -72,6 +104,7 @@ public final class BookReceptacleBlockEntity extends BlockEntity {
         if (!book.isEmpty()) tag.put(BOOK_TAG, book.save(registries));
         if (destination != null) LinkTarget.CODEC.encodeStart(NbtOps.INSTANCE, destination)
                 .result().ifPresent(encoded -> tag.put(DESTINATION_TAG, encoded));
+        if (destination != null) tag.putInt(SKY_COLOR_TAG, skyColor);
     }
 
     @Override public Packet<ClientGamePacketListener> getUpdatePacket() {
@@ -85,6 +118,10 @@ public final class BookReceptacleBlockEntity extends BlockEntity {
     public static void serverTick(net.minecraft.world.level.Level world, BlockPos pos, BlockState state,
                                   BookReceptacleBlockEntity holder) {
         if (!(world instanceof ServerLevel level)) return;
+        // Reconcile receptacles saved before HAS_BOOK existed, including an
+        // occupied receptacle restored from an older pre-release world.
+        boolean hasBook = !holder.book.isEmpty();
+        if (state.getValue(BookReceptacleBlock.HAS_BOOK) != hasBook) holder.sync();
         if (holder.book.isEmpty() || (!holder.restoreView && level.getGameTime() % 200 != 0)) return;
         // Startup maintenance must never turn a saved portal off while its
         // chunks and block entities are still arriving. Structural edits are

src/main/java/net/dnorberg/rivencraft/book/AgeDefinition.java

@@ -28,7 +28,8 @@ public record AgeDefinition(
     public static final ResourceLocation RANDOM_VANILLA_PROFILE = ResourceLocation.fromNamespaceAndPath(
             Rivencraft.MOD_ID, "random_vanilla"
     );
-    public static final int CURRENT_GENERATION_VERSION = 16;
+    public static final int LEGACY_GENERATOR_CUTOFF = 16;
+    public static final int CURRENT_GENERATION_VERSION = AgeSkyProfile.RANDOM_SKY_GENERATION_VERSION;
 
     public AgeDefinition {
         Objects.requireNonNull(id, "id");

src/main/java/net/dnorberg/rivencraft/book/AgeDimensionService.java

@@ -16,6 +16,7 @@ import net.dnorberg.rivencraft.Rivencraft;
 import net.dnorberg.rivencraft.registry.ModBlocks;
 import net.dnorberg.rivencraft.compat.ImmersivePortalsChunkLoaders;
 import net.dnorberg.rivencraft.compat.SereneSeasonsCompatibility;
+import net.dnorberg.rivencraft.compat.RuinsCompatibility;
 import net.dnorberg.rivencraft.compat.TerraBlenderBiomes;
 import net.dnorberg.rivencraft.writing.BiomeSymbolPages;
 import net.dnorberg.rivencraft.writing.BlockSymbolPages;
@@ -84,6 +85,7 @@ public final class AgeDimensionService {
                 if (level != null) {
                     applyCelestialClock(level, age);
                     SereneSeasonsCompatibility.registerAge(server, age);
+                    RuinsCompatibility.registerAge(age);
                 }
             }
             synchronizeImmersivePortals(server);
@@ -141,6 +143,7 @@ public final class AgeDimensionService {
         if (existing != null) {
             applyCelestialClock(existing, definition);
             SereneSeasonsCompatibility.registerAge(server, definition);
+            RuinsCompatibility.registerAge(definition);
             return existing;
         }
 
@@ -157,6 +160,7 @@ public final class AgeDimensionService {
         } else {
             applyCelestialClock(loaded, definition);
             SereneSeasonsCompatibility.registerAge(server, definition);
+            RuinsCompatibility.registerAge(definition);
             synchronizeImmersivePortals(server);
         }
         return loaded;
@@ -352,7 +356,7 @@ public final class AgeDimensionService {
                     server.registryAccess().lookupOrThrow(Registries.STRUCTURE_SET),
                     server.registryAccess().lookupOrThrow(Registries.PLACED_FEATURE)
             );
-            return age.generationVersion() < AgeDefinition.CURRENT_GENERATION_VERSION
+            return age.generationVersion() < AgeDefinition.LEGACY_GENERATOR_CUTOFF
                     ? new FlatLevelSource(settings) : new AgeFlatChunkGenerator(biomeSource, settings, features, age.seed(), libraryAgeSymbols);
         }
         if (profile.terrain() == AgeRuntimeProfile.Terrain.VOID) {
@@ -362,7 +366,7 @@ public final class AgeDimensionService {
                     List.of()
             );
             settings.updateLayers();
-            return age.generationVersion() < AgeDefinition.CURRENT_GENERATION_VERSION
+            return age.generationVersion() < AgeDefinition.LEGACY_GENERATOR_CUTOFF
                     ? new FlatLevelSource(settings) : new AgeFlatChunkGenerator(biomeSource, settings, features, age.seed(), libraryAgeSymbols);
         }
 
@@ -372,7 +376,7 @@ public final class AgeDimensionService {
         NoiseGeneratorSettings baseSettings = noiseSettings.getOrThrow(settingsKey).value();
         Holder<NoiseGeneratorSettings> settings = Holder.direct(withBiomeMaterialRules(baseSettings));
         boolean caveTerrain = AgeBiomeSelection.isCave(profile);
-        return age.generationVersion() < AgeDefinition.CURRENT_GENERATION_VERSION
+        return age.generationVersion() < AgeDefinition.LEGACY_GENERATOR_CUTOFF
                 ? new NoiseBasedChunkGenerator(biomeSource, settings)
                 : new AgeFeatureChunkGenerator(biomeSource, settings, features, age.seed(),
                         caveTerrain, caveTerrain ? TerraBlenderBiomes.nether(server.registryAccess()) : List.of(),
@@ -455,7 +459,7 @@ public final class AgeDimensionService {
             AgeDefinition age,
             AgeRuntimeProfile profile
     ) {
-        if (age.generationVersion() < AgeDefinition.CURRENT_GENERATION_VERSION) {
+        if (age.generationVersion() < AgeDefinition.LEGACY_GENERATOR_CUTOFF) {
             return legacyBiomeSource(server, age, profile);
         }
         AgeBiomeSelection selection = age.plan() != null && age.plan().biomeSelection() != null
@@ -558,7 +562,9 @@ public final class AgeDimensionService {
         DimensionType base = server.registryAccess().lookupOrThrow(Registries.DIMENSION_TYPE)
                 .getOrThrow(ResourceKey.create(Registries.DIMENSION_TYPE, profile.dimensionType())).value();
         AgeTraits.Lighting lighting = age.traits().lighting();
-        boolean hasSkyLight = base.hasSkyLight() && lighting != AgeTraits.Lighting.DARK;
+        AgeSkyProfile sky = AgeSkyProfile.forAge(age);
+        boolean hasSkyLight = (base.hasSkyLight() || !sky.bodies().isEmpty())
+                && lighting != AgeTraits.Lighting.DARK && !age.caveTerrain();
         float ambientLight = lighting == AgeTraits.Lighting.BRIGHT ? 0.25F : 0.0F;
         return new DimensionType(
                 base.fixedTime(),
@@ -573,7 +579,9 @@ public final class AgeDimensionService {
                 base.height(),
                 base.logicalHeight(),
                 base.infiniburn(),
-                AgeEnvironmentCompiler.skyEffects(age.plan(), base.effectsLocation()),
+                age.plan() == null && sky.custom()
+                        ? AgeEnvironmentCompiler.CUSTOM_SKY_EFFECTS
+                        : AgeEnvironmentCompiler.skyEffects(age.plan(), base.effectsLocation()),
                 ambientLight,
                 base.monsterSettings()
         );

src/main/java/net/dnorberg/rivencraft/book/AgeEnvironmentCompiler.java

@@ -2,10 +2,16 @@ package net.dnorberg.rivencraft.book;
 
 import net.dnorberg.rivencraft.writing.SymbolSemantics;
 import net.minecraft.resources.ResourceLocation;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.resources.ResourceKey;
 import net.minecraft.world.level.dimension.BuiltinDimensionTypes;
 
 /** Resolves written environment pages without changing the seeded page-free Age path. */
 public final class AgeEnvironmentCompiler {
+    public static final ResourceLocation CUSTOM_SKY_EFFECTS = ResourceLocation.fromNamespaceAndPath(
+            "rivencraft", "custom_sky");
     private AgeEnvironmentCompiler() {}
 
     public static AgeTraits apply(AgeGenerationPlan plan, AgeTraits seeded) {
@@ -19,6 +25,7 @@ public final class AgeEnvironmentCompiler {
         } else {
             applied = applyLegacy(plan, seeded);
         }
+        AgeSkyProfile.compile(plan, applied);
         return forTerrain(applied, plan.runtimeProfile());
     }
 
@@ -67,8 +74,7 @@ public final class AgeEnvironmentCompiler {
                     phaseDegrees = writtenPhase ? circularMidpoint(phaseDegrees, next) : next;
                     writtenPhase = true;
                 }
-                case ANGLE_MODIFIER -> throw new IllegalArgumentException(
-                        "Sun angle pages require a custom sky renderer and are not supported yet");
+                case ANGLE_MODIFIER -> { } // Consumed by the next independently rendered celestial.
                 default -> { }
             }
         }
@@ -81,6 +87,8 @@ public final class AgeEnvironmentCompiler {
     /** Vanilla effects are the sky styles the current renderer can honor exactly. */
     public static ResourceLocation skyEffects(AgeGenerationPlan plan, ResourceLocation fallback) {
         if (plan == null) return fallback;
+        if (skyColor(plan) != -1 || staticSky(plan) || AgeSkyProfile.hasCustomCelestials(plan))
+            return CUSTOM_SKY_EFFECTS;
         return plan.activeSymbols().stream()
                 .filter(symbol -> symbol.semantics().role() == SymbolSemantics.Role.SKY)
                 .map(symbol -> ((SymbolSemantics.ChoiceValue) symbol.semantics().value()).id())
@@ -92,6 +100,48 @@ public final class AgeEnvironmentCompiler {
                 }).findFirst().orElse(fallback);
     }
 
+    public static boolean staticSky(AgeGenerationPlan plan) {
+        return plan != null && plan.activeSymbols().stream().anyMatch(symbol ->
+                symbol.semantics().role() == SymbolSemantics.Role.SKY
+                        && ((SymbolSemantics.ChoiceValue) symbol.semantics().value()).id().equals("static"));
+    }
+
+    /** An authored color is fixed; -1 means the biome or selected vanilla sky supplies it. */
+    public static int skyColor(AgeGenerationPlan plan) {
+        return AgeSkyProfile.authoredSkyColor(plan);
+    }
+
+    public static int selectedSkyColor(AgeGenerationPlan plan, ResourceLocation fallback, int biomeSkyColor) {
+        int authored = skyColor(plan);
+        if (authored != -1) return authored;
+        if (staticSky(plan)) return 0xFF929292;
+        ResourceLocation effects = skyEffects(plan, fallback);
+        return previewSkyColor(effects, biomeSkyColor);
+    }
+
+    /** Shared server answer for book previews and the fallback crystal portal surface. */
+    public static int previewSkyColor(ServerLevel level, BlockPos origin) {
+        int biomeColor = level.getBiome(origin).value().getSkyColor();
+        var age = AgeRegistrySavedData.get(level).definitions().stream()
+                .filter(candidate -> AgeDimensionService.dimensionKey(candidate).equals(level.dimension()))
+                .findFirst();
+        if (age.isEmpty()) return previewSkyColor(level.dimensionType().effectsLocation(), biomeColor);
+        var definition = age.orElseThrow();
+        AgeSkyProfile sky = AgeSkyProfile.forAge(definition);
+        if (definition.plan() == null && definition.generationVersion() >= AgeSkyProfile.RANDOM_SKY_GENERATION_VERSION) {
+            if (sky.color() != -1) return sky.color();
+            if (sky.style() == AgeSkyProfile.Style.STATIC) return 0xFF929292;
+        }
+        var profile = definition.plan() == null
+                ? AgeRuntimeProfiles.resolve(definition.generationProfile())
+                : definition.plan().runtimeProfile();
+        ResourceLocation baseEffects = level.getServer().registryAccess()
+                .lookupOrThrow(Registries.DIMENSION_TYPE)
+                .getOrThrow(ResourceKey.create(Registries.DIMENSION_TYPE, profile.dimensionType()))
+                .value().effectsLocation();
+        return selectedSkyColor(definition.plan(), baseEffects, biomeColor);
+    }
+
     public static boolean hasWrittenPhase(AgeGenerationPlan plan) {
         if (plan == null) return false;
         if (plan.version() >= 4) return orderedCelestial(plan, null).writtenPhase();

src/main/java/net/dnorberg/rivencraft/book/AgeFeatureSelection.java

@@ -10,6 +10,7 @@ import java.util.Map;
 import java.util.Optional;
 import java.util.Random;
 import net.dnorberg.rivencraft.writing.BlockSymbolPages;
+import net.dnorberg.rivencraft.compat.RuinsTemplatePages;
 import net.dnorberg.rivencraft.writing.OrderedWriting;
 import net.dnorberg.rivencraft.writing.SymbolSemantics;
 import net.dnorberg.rivencraft.writing.WritingGrammar;
@@ -235,6 +236,9 @@ public final class AgeFeatureSelection {
     }
 
     public static String error(ResourceLocation choice, AgeRuntimeProfile profile, RegistryAccess registries) {
+        if (RuinsTemplatePages.isSymbol(choice))
+            return RuinsTemplatePages.contains(choice) ? null : "Ruins template " + choice
+                    + " is unavailable; restore Ruins and its template before loading this Age";
         if (AgeStructureSelection.feature(choice))
             return AgeStructureSelection.error(choice, profile, null, registries);
         if (choice.equals(AgeDenseOres.ID))

src/main/java/net/dnorberg/rivencraft/book/AgeGenerationPlan.java

@@ -188,7 +188,7 @@ public record AgeGenerationPlan(int version, long ageSeed, OrderedWriting writin
             String raw = item.getString("Value");
             SymbolSemantics.Value value = switch (role) {
                 case TERRAIN, BIOME, BLOCK, FEATURE -> new SymbolSemantics.ResourceValue(ResourceLocation.parse(raw));
-                case PERIOD_MODIFIER, ANGLE_MODIFIER, PHASE_MODIFIER ->
+                case PERIOD_MODIFIER, ANGLE_MODIFIER, PHASE_MODIFIER, SIZE_MODIFIER, COLOR_NUMBER ->
                         new SymbolSemantics.NumberValue(Double.parseDouble(raw));
                 default -> new SymbolSemantics.ChoiceValue(raw);
             };

src/main/java/net/dnorberg/rivencraft/book/AgeInstability.java

@@ -6,6 +6,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.Objects;
 import net.dnorberg.rivencraft.writing.WritingGrammar;
+import net.dnorberg.rivencraft.compat.RuinsTemplatePages;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.ListTag;
@@ -51,6 +52,10 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
     }
 
     static AgeInstability compute(AgeGenerationPlan plan, AgeTraits traits, RegistryAccess registries) {
+        return compute(plan, traits, registries, Long.MIN_VALUE);
+    }
+
+    static AgeInstability compute(AgeGenerationPlan plan, AgeTraits traits, RegistryAccess registries, long ageSeed) {
         Objects.requireNonNull(traits, "traits");
         List<Contribution> contributions = new ArrayList<>();
         if (plan == null) {
@@ -82,6 +87,17 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
             contributions.add(new Contribution("bright_lighting", -1, BRIGHT_LIGHTING_COST,
                     "Seeded bright lighting"));
         }
+        AgeSkyProfile sky = plan == null && ageSeed != Long.MIN_VALUE ? AgeSkyProfile.random(ageSeed, traits)
+                : plan == null ? new AgeSkyProfile(AgeSkyProfile.Style.INHERITED, -1, List.of())
+                : AgeSkyProfile.compile(plan, traits);
+        int seenSuns = 0;
+        for (AgeSkyProfile.Body body : sky.bodies()) {
+            if (body.kind() != AgeSkyProfile.Kind.SUN) continue;
+            if (++seenSuns <= 2) continue;
+            int points = 1000 * (seenSuns - 2);
+            contributions.add(new Contribution("extra_sun", -1, points,
+                    "Sun " + seenSuns + " adds growing instability"));
+        }
         return new AgeInstability(CURRENT_VERSION,
                 contributions.stream().mapToInt(Contribution::points).sum(), contributions);
     }
@@ -94,7 +110,8 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
             if (cave) {
                 var role = symbol.semantics().role();
                 if (switch (role) {
-                    case WEATHER, SEASON, CELESTIAL, PERIOD_MODIFIER, PHASE_MODIFIER, ANGLE_MODIFIER -> true;
+                    case WEATHER, SEASON, CELESTIAL, PERIOD_MODIFIER, PHASE_MODIFIER,
+                            ANGLE_MODIFIER, DIRECTION_MODIFIER -> true;
                     default -> false;
                 }) {
                     contributions.add(new Contribution("cave_ignored_" + role.id(), symbol.index(),
@@ -134,9 +151,12 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
                     || !(symbol.semantics().value()
                     instanceof net.dnorberg.rivencraft.writing.SymbolSemantics.ResourceValue resource)) continue;
             String name = COUNTED_STRUCTURES.get(resource.id());
+            if (name == null && RuinsTemplatePages.isSymbol(resource.id()))
+                name = RuinsTemplatePages.fallbackName(resource.id());
             if (name == null) continue;
             int count = structureCounts.merge(resource.id(), 1, Integer::sum);
-            if (AgeStructureSelection.requiresBiomeOverride(resource.id(), plan.biomeSelection(), registries)) {
+            if (COUNTED_STRUCTURES.containsKey(resource.id())
+                    && AgeStructureSelection.requiresBiomeOverride(resource.id(), plan.biomeSelection(), registries)) {
                 contributions.add(new Contribution("forced_biome_" + resource.id().getPath(), symbol.index(),
                         FORCED_STRUCTURE_BIOME_COST,
                         name + " occurrence " + count + " is forced into an unsupported biome"));
@@ -152,7 +172,7 @@ public record AgeInstability(int version, int score, List<Contribution> breakdow
 
     static int featureCost(ResourceLocation feature, int occurrence) {
         if (occurrence < 1) throw new IllegalArgumentException("Feature occurrence must be positive");
-        return COUNTED_STRUCTURES.containsKey(feature) && occurrence > 3
+        return (COUNTED_STRUCTURES.containsKey(feature) || RuinsTemplatePages.isSymbol(feature)) && occurrence > 3
                 ? EXCESS_LEGACY_STRUCTURE_COST : 0;
     }
 

src/main/java/net/dnorberg/rivencraft/book/AgePersistenceGameTests.java

@@ -125,9 +125,9 @@ public final class AgePersistenceGameTests {
                 new AgeReference(UUID.randomUUID(), "Stable Writing"), stable);
         AgeDefinition defectiveAge = AgeRegistrySavedData.resolveOrCreate(helper.getLevel(),
                 new AgeReference(UUID.randomUUID(), "Defective Writing"), defective);
-        helper.assertValueEqual(stableAge.instability().score(), 0,
+        helper.assertValueEqual(nonCelestialInstability(stableAge), 0,
                 "Missing seeded branches do not add instability");
-        helper.assertValueEqual(defectiveAge.instability().score(), 600,
+        helper.assertValueEqual(nonCelestialInstability(defectiveAge), 600,
                 "Out-of-order and repeated terrain pages each add their saved penalty");
         helper.assertTrue(defectiveAge.instability().breakdown().stream()
                         .anyMatch(part -> part.reason().equals("duplicate") && part.pageIndex() == 3),
@@ -184,9 +184,9 @@ public final class AgePersistenceGameTests {
                     new AgeReference(UUID.randomUUID(), "Three " + structure), structureWriting(structure, 3));
             AgeDefinition four = AgeRegistrySavedData.resolveOrCreate(helper.getLevel(),
                     new AgeReference(UUID.randomUUID(), "Four " + structure), structureWriting(structure, 4));
-            helper.assertValueEqual(three.instability().score(), 0,
+            helper.assertValueEqual(nonCelestialInstability(three), 0,
                     "The first three " + structure + " pages retain Legacy's zero cost");
-            helper.assertValueEqual(four.instability().score(), 100,
+            helper.assertValueEqual(nonCelestialInstability(four), 100,
                     "The fourth " + structure + " page must add Legacy's 100-point cost");
             helper.assertTrue(four.instability().breakdown().stream().anyMatch(part ->
                             part.reason().equals("excess_" + structure) && part.pageIndex() == 8),
@@ -207,6 +207,13 @@ public final class AgePersistenceGameTests {
                 "Modern repeated structures must use the same deterministic scoring path");
         helper.assertValueEqual(AgeInstability.featureCost(ResourceLocation.parse("rivencraft:dungeons"), 4), 0,
                 "A Legacy-neutral feature must remain neutral when repeated");
+        ResourceLocation ruin = net.dnorberg.rivencraft.compat.RuinsTemplatePages.symbolId("ZombieHut.tml");
+        helper.assertValueEqual(AgeInstability.featureCost(ruin, 1), 0,
+                "The first Ruins template page is free like a standard structure");
+        helper.assertValueEqual(AgeInstability.featureCost(ruin, 3), 0,
+                "The first three copies of a Ruins page are free");
+        helper.assertValueEqual(AgeInstability.featureCost(ruin, 4), 100,
+                "Each Ruins page beyond the third adds 100 instability");
 
         OrderedWriting duplicateBright = new OrderedWriting(List.of(
                 WritingEntry.linkPanel(),
@@ -216,7 +223,7 @@ public final class AgePersistenceGameTests {
         ));
         AgeDefinition bright = AgeRegistrySavedData.resolveOrCreate(helper.getLevel(),
                 new AgeReference(UUID.randomUUID(), "Double Bright"), duplicateBright);
-        helper.assertValueEqual(bright.instability().score(), 1500,
+        helper.assertValueEqual(nonCelestialInstability(bright), 1500,
                 "Each Bright Lighting page costs 500 and the extra controller costs another 500");
         helper.assertValueEqual(bright.instability().breakdown().stream()
                         .filter(part -> part.reason().equals("bright_lighting")).count(), 2L,
@@ -420,6 +427,13 @@ public final class AgePersistenceGameTests {
         helper.succeed();
     }
 
+    /** Isolate the writing-cost assertion from seed-completed extra-sun instability. */
+    private static int nonCelestialInstability(AgeDefinition age) {
+        return age.instability().breakdown().stream()
+                .filter(part -> !part.reason().equals("extra_sun"))
+                .mapToInt(AgeInstability.Contribution::points).sum();
+    }
+
     private static CompoundTag entry(
             UUID id,
             String name,

src/main/java/net/dnorberg/rivencraft/book/AgeRegistrySavedData.java

@@ -179,7 +179,7 @@ public final class AgeRegistrySavedData extends SavedData {
         AgeTraits effectiveTraits = plan == null
                 ? AgeEnvironmentCompiler.forTerrain(traits, AgeRuntimeProfiles.resolve(seedProfile))
                 : AgeEnvironmentCompiler.apply(plan, traits);
-        AgeInstability instability = AgeInstability.compute(plan, effectiveTraits, registries);
+        AgeInstability instability = AgeInstability.compute(plan, effectiveTraits, registries, seed);
         AgeInstabilityPlan instabilityPlan = AgeInstabilityPlan.select(instability, seed);
         AgeDefinition created = new AgeDefinition(
                 reference.id(),

src/main/java/net/dnorberg/rivencraft/book/AgeSkyProfile.java

@@ -0,0 +1,324 @@
+package net.dnorberg.rivencraft.book;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Random;
+import java.util.Set;
+import net.dnorberg.rivencraft.writing.SymbolSemantics;
+
+/** The ordered, deterministic sky specification for an Age. No client data is trusted here. */
+public record AgeSkyProfile(Style style, int color, List<Body> bodies) {
+    public static final int RANDOM_SKY_GENERATION_VERSION = 17;
+    private static final int[] COLORS = {0xB74A50, 0xD9834B, 0xDBC574, 0x5AAB80,
+            0x6FA8DF, 0x9870B9, 0xD5DBE1, 0x252531};
+
+    public AgeSkyProfile {
+        bodies = List.copyOf(bodies);
+        long suns = bodies.stream().filter(body -> body.kind() == Kind.SUN).count();
+        long moons = bodies.size() - suns;
+        if (suns > 10 || moons > 10) throw new IllegalArgumentException("An Age may have at most ten suns and ten moons");
+    }
+
+    public static AgeSkyProfile forAge(AgeDefinition age) {
+        if (age.plan() != null) return compile(age.plan(), age.traits());
+        if (age.generationVersion() >= RANDOM_SKY_GENERATION_VERSION)
+            return random(age.seed(), age.traits());
+        return new AgeSkyProfile(Style.INHERITED, -1, List.of());
+    }
+
+    public static AgeSkyProfile random(long seed, AgeTraits traits) {
+        Random random = new Random(seed ^ 0x534B5950524F464CL);
+        Style style = Style.values()[random.nextInt(Style.values().length)];
+        int color = randomColor(random);
+        int suns = random.nextInt(4);
+        int moons = random.nextInt(4);
+        List<Body> bodies = new ArrayList<>();
+        for (int i = 0; i < suns; i++)
+            bodies.add(new Body(Kind.SUN, randomColor(random),
+                    0.75F + random.nextFloat(), random.nextFloat() * 360.0F,
+                    traits.celestialPeriod(), random.nextFloat(), random.nextBoolean()));
+        for (int i = 0; i < moons; i++)
+            bodies.add(new Body(Kind.MOON, randomColor(random),
+                    0.75F + random.nextFloat(), random.nextFloat() * 360.0F,
+                    traits.celestialPeriod(), random.nextFloat(), random.nextBoolean()));
+        return new AgeSkyProfile(style, color, bodies);
+    }
+
+    public static AgeSkyProfile compile(AgeGenerationPlan plan, AgeTraits traits) {
+        if (plan == null) return new AgeSkyProfile(Style.INHERITED, -1, List.of());
+        Style style = Style.INHERITED;
+        int color = authoredSkyColor(plan);
+        boolean customBodies = hasCustomCelestials(plan);
+        List<Body> bodies = new ArrayList<>();
+        Set<Integer> active = new HashSet<>(plan.activeSymbolIndices());
+        AgeTraits seeded = AgeTraits.select(plan.ageSeed());
+        double period = 1.0D;
+        float angle = seeded.celestialAngle();
+        float phase = seeded.celestialPhase();
+        float size = 1.0F;
+        List<Integer> bodyColors = new ArrayList<>();
+        ColorAccumulator pendingColors = new ColorAccumulator();
+        Integer colorMultiplier = null;
+        boolean clockwise = true;
+        for (AgeGenerationPlan.ResolvedSymbol symbol : plan.symbols()) {
+            if (!active.contains(symbol.index())) continue;
+            SymbolSemantics semantics = symbol.semantics();
+            if (semantics.role() != SymbolSemantics.Role.COLOR
+                    && semantics.role() != SymbolSemantics.Role.COLOR_NUMBER) colorMultiplier = null;
+            switch (semantics.role()) {
+                case SKY -> {
+                    pendingColors.clear();
+                    style = switch (((SymbolSemantics.ChoiceValue) semantics.value()).id()) {
+                        case "overworld" -> Style.OVERWORLD;
+                        case "nether" -> Style.NETHER;
+                        case "end" -> Style.END;
+                        case "static" -> Style.STATIC;
+                        default -> throw new IllegalArgumentException("Unknown sky style");
+                    };
+                }
+                case COLOR_NUMBER -> colorMultiplier = (int) ((SymbolSemantics.NumberValue)
+                        semantics.value()).amount();
+                case COLOR -> {
+                    pendingColors.add(((SymbolSemantics.ChoiceValue) semantics.value()).id(),
+                            colorMultiplier == null ? randomColorNumber(plan.ageSeed(), symbol.index()) : colorMultiplier);
+                    colorMultiplier = null;
+                }
+                case PERIOD_MODIFIER -> period = ((SymbolSemantics.NumberValue) semantics.value()).amount();
+                case ANGLE_MODIFIER -> angle = (float) ((SymbolSemantics.NumberValue) semantics.value()).amount();
+                case PHASE_MODIFIER -> phase = (float) (((SymbolSemantics.NumberValue) semantics.value()).amount() / 360.0D);
+                case SIZE_MODIFIER -> size = (float) ((SymbolSemantics.NumberValue) semantics.value()).amount();
+                case CELESTIAL_COLOR -> bodyColors.add(color(
+                        ((SymbolSemantics.ChoiceValue) semantics.value()).id()));
+                case DIRECTION_MODIFIER -> clockwise = ((SymbolSemantics.ChoiceValue) semantics.value())
+                        .id().equals("clockwise");
+                case CELESTIAL -> {
+                    String choice = ((SymbolSemantics.ChoiceValue) semantics.value()).id();
+                    int bodyColor = pendingColors.written() ? pendingColors.rgb()
+                            : bodyColors.isEmpty() ? 0 : mixColors(bodyColors);
+                    if (choice.equals("normal_time")) {
+                        if (customBodies) {
+                            bodies.add(new Body(Kind.SUN, bodyColor, size, angle, period, phase, clockwise));
+                            bodies.add(new Body(Kind.MOON, bodyColor, 1.0F, angle, period,
+                                    (phase + 0.5F) % 1.0F, clockwise));
+                        }
+                    } else {
+                        bodies.add(new Body(choice.equals("sun") ? Kind.SUN : Kind.MOON,
+                                bodyColor, size, angle, period, phase, clockwise));
+                    }
+                    period = 1.0D;
+                    angle = seeded.celestialAngle();
+                    phase = seeded.celestialPhase();
+                    size = 1.0F;
+                    bodyColors.clear();
+                    pendingColors.clear();
+                    clockwise = true;
+                }
+                default -> { }
+            }
+        }
+        // Missing branches are seed-completed, including the celestial branch.
+        // An explicit sky or sky-color page does not suppress that completion.
+        if (plan.activeSymbols().stream().noneMatch(symbol ->
+                symbol.semantics().role() == SymbolSemantics.Role.CELESTIAL)) {
+            bodies.addAll(random(plan.ageSeed(), seeded).bodies());
+        }
+        return new AgeSkyProfile(style, color, bodies);
+    }
+
+    public static int mixColors(List<Integer> colors) {
+        if (colors.isEmpty()) return -1;
+        long red = 0, green = 0, blue = 0;
+        for (int color : colors) {
+            red += color >> 16 & 255;
+            green += color >> 8 & 255;
+            blue += color & 255;
+        }
+        int count = colors.size();
+        return (int) ((red + count / 2) / count) << 16
+                | (int) ((green + count / 2) / count) << 8
+                | (int) ((blue + count / 2) / count);
+    }
+
+    /** Shared color pages affect the next Sky or celestial page; trailing colors tint the sky. */
+    public static int authoredSkyColor(AgeGenerationPlan plan) {
+        if (plan == null) return -1;
+        ColorAccumulator pending = new ColorAccumulator();
+        Integer multiplier = null;
+        int skyColor = -1;
+        List<Integer> legacyColors = new ArrayList<>();
+        Set<Integer> active = new HashSet<>(plan.activeSymbolIndices());
+        for (AgeGenerationPlan.ResolvedSymbol symbol : plan.symbols()) {
+            if (!active.contains(symbol.index())) continue;
+            SymbolSemantics semantics = symbol.semantics();
+            if (semantics.role() != SymbolSemantics.Role.COLOR
+                    && semantics.role() != SymbolSemantics.Role.COLOR_NUMBER) multiplier = null;
+            switch (semantics.role()) {
+                case COLOR_NUMBER -> multiplier = (int) ((SymbolSemantics.NumberValue) semantics.value()).amount();
+                case COLOR -> {
+                    pending.add(((SymbolSemantics.ChoiceValue) semantics.value()).id(),
+                            multiplier == null ? randomColorNumber(plan.ageSeed(), symbol.index()) : multiplier);
+                    multiplier = null;
+                }
+                case SKY -> {
+                    if (pending.written()) skyColor = pending.rgb();
+                    pending.clear();
+                }
+                case CELESTIAL -> pending.clear();
+                case SKY_COLOR -> legacyColors.add(color(
+                        ((SymbolSemantics.ChoiceValue) semantics.value()).id()));
+                default -> { }
+            }
+        }
+        if (pending.written()) skyColor = pending.rgb();
+        return skyColor != -1 ? skyColor : mixColors(legacyColors);
+    }
+
+    private static int randomColorNumber(long ageSeed, int pageIndex) {
+        return new Random(ageSeed ^ (0x9E3779B97F4A7C15L * (pageIndex + 1L))).nextInt(25);
+    }
+
+    private static final class ColorAccumulator {
+        private int red;
+        private int green;
+        private int blue;
+        private boolean written;
+
+        void add(String color, int multiplier) {
+            int amount = multiplier * 10;
+            written = true;
+            switch (color) {
+                case "red" -> red += amount;
+                case "green" -> green += amount;
+                case "blue" -> blue += amount;
+                case "white" -> { red += amount; green += amount; blue += amount; }
+                case "black" -> { red -= amount; green -= amount; blue -= amount; }
+                default -> throw new IllegalArgumentException("Unknown shared color " + color);
+            }
+        }
+
+        boolean written() { return written; }
+
+        int rgb() {
+            return clamp(red) << 16 | clamp(green) << 8 | clamp(blue);
+        }
+
+        void clear() { red = green = blue = 0; written = false; }
+
+        private static int clamp(int channel) { return Math.max(0, Math.min(255, channel)); }
+    }
+
+    private static int randomColor(Random random) {
+        int count = 1 + random.nextInt(3);
+        List<Integer> colors = new ArrayList<>(count);
+        for (int i = 0; i < count; i++) colors.add(COLORS[random.nextInt(COLORS.length)]);
+        return mixColors(colors);
+    }
+
+    public static boolean hasCustomCelestials(AgeGenerationPlan plan) {
+        return plan != null && (hasColorForCelestial(plan) || plan.activeSymbols().stream().anyMatch(symbol ->
+                symbol.semantics().role() == SymbolSemantics.Role.CELESTIAL
+                        && !((SymbolSemantics.ChoiceValue) symbol.semantics().value()).id().equals("normal_time")
+                        || symbol.semantics().role() == SymbolSemantics.Role.CELESTIAL_COLOR
+                        || symbol.semantics().role() == SymbolSemantics.Role.SIZE_MODIFIER
+                        || symbol.semantics().role() == SymbolSemantics.Role.DIRECTION_MODIFIER));
+    }
+
+    private static boolean hasColorForCelestial(AgeGenerationPlan plan) {
+        Set<Integer> active = new HashSet<>(plan.activeSymbolIndices());
+        boolean pending = false;
+        for (AgeGenerationPlan.ResolvedSymbol symbol : plan.symbols()) {
+            if (!active.contains(symbol.index())) continue;
+            switch (symbol.semantics().role()) {
+                case COLOR -> pending = true;
+                case SKY -> pending = false;
+                case CELESTIAL -> {
+                    if (pending) return true;
+                    pending = false;
+                }
+                default -> { }
+            }
+        }
+        return false;
+    }
+
+    public boolean custom() {
+        return style == Style.STATIC || color != -1 || !bodies.isEmpty();
+    }
+
+    /** Vanilla has one skylight channel; combine visible bodies into that channel. */
+    public float lightAt(double dayTime) {
+        float sunlight = 0.0F;
+        float moonlight = 0.0F;
+        for (Body body : bodies) {
+            double orbit = body.period() == 0.0D ? body.phase()
+                    : (body.clockwise() ? 1.0D : -1.0D) * dayTime
+                            / (24000.0D * body.period()) + body.phase();
+            float altitude = (float) Math.cos(orbit * Math.PI * 2.0D);
+            if (altitude <= 0.0F) continue;
+            if (body.kind() == Kind.SUN) sunlight += altitude * (1.0F - 0.85F * eclipseFor(body, dayTime));
+            else moonlight += altitude * 0.18F;
+        }
+        return Math.min(1.0F, sunlight > 0.0F ? sunlight : moonlight);
+    }
+
+    /** Disc overlap in the rendered sky, from first contact (0) to centered alignment (1). */
+    public float eclipseFor(Body body, double dayTime) {
+        float strongest = 0.0F;
+        net.minecraft.world.phys.Vec3 bodyDirection = direction(body, dayTime);
+        for (Body other : bodies) {
+            if (other.kind() == body.kind()) continue;
+            double dot = Math.max(-1.0D, Math.min(1.0D,
+                    bodyDirection.dot(direction(other, dayTime))));
+            double separation = Math.acos(dot);
+            // The outer 32x32 quad is only glow. The opaque body occupies its
+            // central 8x8 pixels, so contact must use one quarter of its size.
+            double radius = Math.atan((body.kind() == Kind.SUN ? 30.0D : 20.0D)
+                    * body.size() * 0.25D / 100.0D)
+                    + Math.atan((other.kind() == Kind.SUN ? 30.0D : 20.0D)
+                    * other.size() * 0.25D / 100.0D);
+            if (radius > 0.0D) strongest = Math.max(strongest,
+                    (float) Math.max(0.0D, 1.0D - separation / radius));
+        }
+        return strongest;
+    }
+
+    public float eclipseAt(double dayTime) {
+        float strongest = 0.0F;
+        for (Body body : bodies) {
+            if (body.kind() == Kind.SUN && direction(body, dayTime).y > 0.0D)
+                strongest = Math.max(strongest, eclipseFor(body, dayTime));
+        }
+        return strongest;
+    }
+
+    private static net.minecraft.world.phys.Vec3 direction(Body body, double dayTime) {
+        double orbit = body.period() == 0.0D ? body.phase()
+                : (body.clockwise() ? 1.0D : -1.0D) * dayTime
+                        / (24000.0D * body.period()) + body.phase();
+        double tilt = orbit * Math.PI * 2.0D;
+        double bearing = Math.toRadians(body.angle());
+        double lateral = Math.sin(tilt);
+        return new net.minecraft.world.phys.Vec3(
+                Math.sin(bearing) * lateral, Math.cos(tilt), Math.cos(bearing) * lateral);
+    }
+
+    public static int color(String name) {
+        return switch (name) {
+            case "red" -> COLORS[0];
+            case "orange" -> COLORS[1];
+            case "yellow" -> COLORS[2];
+            case "green" -> COLORS[3];
+            case "blue" -> COLORS[4];
+            case "purple" -> COLORS[5];
+            case "white" -> COLORS[6];
+            case "black" -> COLORS[7];
+            default -> throw new IllegalArgumentException("Unknown sky color " + name);
+        };
+    }
+
+    public enum Style { INHERITED, OVERWORLD, NETHER, END, STATIC }
+    public enum Kind { SUN, MOON }
+    public record Body(Kind kind, int color, float size, float angle,
+                       double period, float phase, boolean clockwise) { }
+}

src/main/java/net/dnorberg/rivencraft/book/EnvironmentWritingGameTests.java

@@ -52,9 +52,12 @@ public final class EnvironmentWritingGameTests {
     public static void environmentPagesEnterCreativeAndJeiFeed(GameTestHelper helper) {
         Set<String> expected = Set.of(
                 "lighting/normal", "lighting/dark", "lighting/bright",
-                "sky/overworld", "sky/nether", "sky/end",
+                "sky/overworld", "sky/nether", "sky/end", "sky/static", "color/red", "color/green",
+                "color/blue", "color/black", "color/white", "number/0", "number/24",
                 "weather/normal", "weather/fast", "weather/slow", "weather/off",
-                "weather/always", "weather/storm", "celestial/normal_time",
+                "weather/always", "weather/storm", "celestial/normal_time", "celestial/sun",
+                "celestial/moon", "size/large", "angle/east",
+                "direction/clockwise", "direction/counterclockwise",
                 "season/no_seasons", "season/seasons", "season/eternal_winter",
                 "season/eternal_summer", "season/eternal_fall", "season/eternal_spring",
                 "period/zero", "period/half", "period/full", "period/double",
@@ -67,6 +70,9 @@ public final class EnvironmentWritingGameTests {
         helper.assertTrue(PageItem.bundledCreativeSymbols().containsAll(expected)
                         && creative.containsAll(expected),
                 "Every supported environment page must enter the creative index JEI also consumes");
+        helper.assertValueEqual(PageItem.bundledCreativeSymbols().stream()
+                        .filter(path -> path.startsWith("number/")).count(), 25L,
+                "Creative and JEI must expose all 25 D'ni number pages");
         for (String path : expected) {
             var id = ResourceLocation.fromNamespaceAndPath("rivencraft", path);
             helper.assertTrue(SymbolCatalog.isKnown(new SymbolReference(id))
@@ -135,6 +141,156 @@ public final class EnvironmentWritingGameTests {
         helper.succeed();
     }
 
+    @GameTest(template = "empty")
+    public static void authoredStaticSkyColorSurvivesWritingAndFeedsPreview(GameTestHelper helper) {
+        OrderedWriting writing = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(), page("terrain/standard"), page("number/20"),
+                page("color/blue"), page("sky/static"), page("celestial/normal_time")));
+        AgeTraits seeded = AgeTraits.select(44L);
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, 44L, AgeGenerationProfiles.STANDARD,
+                seeded, helper.getLevel().registryAccess());
+        helper.assertTrue(AgeEnvironmentCompiler.staticSky(plan),
+                "The authored Static Sky page must survive Age compilation");
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyEffects(plan, BuiltinDimensionTypes.OVERWORLD_EFFECTS),
+                AgeEnvironmentCompiler.CUSTOM_SKY_EFFECTS,
+                "The static sky must select Rivencraft's custom renderer");
+        helper.assertValueEqual(AgeEnvironmentCompiler.selectedSkyColor(plan,
+                        BuiltinDimensionTypes.OVERWORLD_EFFECTS, 0xFF77AAFF),
+                0x0000C8, "The authored color must tint the sky and preview consistently");
+        AgeGenerationPlan restored = AgeGenerationPlan.load(plan.save());
+        helper.assertTrue(AgeEnvironmentCompiler.staticSky(restored),
+                "A saved Age must retain its static sky choice");
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyColor(restored), 0x0000C8,
+                "A saved Age must retain its sky color choice");
+        AgeGenerationPlan coloredEnd = AgeGenerationPlan.compile(new OrderedWriting(List.of(
+                        WritingEntry.linkPanel(), page("terrain/standard"), page("number/15"),
+                        page("color/red"), page("sky/end"), page("celestial/normal_time"))),
+                45L, AgeGenerationProfiles.STANDARD, AgeTraits.select(45L),
+                helper.getLevel().registryAccess());
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyEffects(coloredEnd,
+                        BuiltinDimensionTypes.OVERWORLD_EFFECTS),
+                AgeEnvironmentCompiler.CUSTOM_SKY_EFFECTS,
+                "A color page must make non-Overworld skies renderable by the custom sky effect");
+        helper.assertValueEqual(AgeEnvironmentCompiler.selectedSkyColor(coloredEnd,
+                        BuiltinDimensionTypes.OVERWORLD_EFFECTS, 0xFF77AAFF),
+                0x960000, "A color page must override the selected sky type's default tint");
+        helper.assertTrue(PageItem.bundledCreativeSymbols().contains("sky/static")
+                        && PageItem.bundledCreativeSymbols().contains("color/blue")
+                        && PageItem.bundledCreativeSymbols().contains("number/24"),
+                "New sky pages must be available through the Creative and JEI page catalog");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void skyAndCelestialColorsBlendWithoutRequiringBodies(GameTestHelper helper) {
+        OrderedWriting writing = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(), page("terrain/standard"),
+                page("number/10"), page("color/red"), page("number/5"), page("color/blue"),
+                page("sky/overworld"), page("number/12"), page("color/green"),
+                page("number/7"), page("color/blue"), page("celestial/sun")));
+        helper.assertTrue(WritingGrammar.parse(writing).canCreate(),
+                "Two sky colors and two colors for one sun must be valid writing");
+        AgeTraits traits = AgeTraits.select(46L);
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, 46L,
+                AgeGenerationProfiles.STANDARD, traits, helper.getLevel().registryAccess());
+        int skyColor = 0x640032;
+        int sunColor = 0x007846;
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyColor(plan), skyColor,
+                "Sky color pages must blend without discarding either page");
+        AgeSkyProfile profile = AgeSkyProfile.compile(plan, traits);
+        helper.assertValueEqual(profile.bodies().size(), 1, "The written Age has exactly one sun");
+        helper.assertValueEqual(profile.bodies().getFirst().color(), sunColor,
+                "Celestial colors must blend for the following body");
+        helper.assertValueEqual(AgeSkyProfile.compile(AgeGenerationPlan.load(plan.save()), traits), profile,
+                "Blended colors must survive the saved writing plan");
+
+        AgeSkyProfile bodyless = new AgeSkyProfile(AgeSkyProfile.Style.OVERWORLD, skyColor, List.of());
+        helper.assertTrue(bodyless.custom() && bodyless.bodies().isEmpty(),
+                "An Age can have an authored sky without any celestial bodies");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void colorNumbersUseDniDigitsAndMissingChannelsRemainZero(GameTestHelper helper) {
+        OrderedWriting writing = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(), page("number/12"), page("color/red"),
+                page("number/5"), page("color/white"), page("number/3"), page("color/black"),
+                page("sky/overworld")));
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, 49L,
+                AgeGenerationProfiles.STANDARD, AgeTraits.select(49L), helper.getLevel().registryAccess());
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyColor(plan), 0x8C1414,
+                "White adds and Black subtracts from every channel; missing green and blue start at zero");
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyColor(AgeGenerationPlan.load(plan.save())), 0x8C1414,
+                "D'ni color multipliers must remain frozen in a saved Age plan");
+
+        OrderedWriting unnumbered = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(), page("color/green"), page("sky/overworld")));
+        AgeGenerationPlan randomPlan = AgeGenerationPlan.compile(unnumbered, 50L,
+                AgeGenerationProfiles.STANDARD, AgeTraits.select(50L), helper.getLevel().registryAccess());
+        int color = AgeEnvironmentCompiler.skyColor(randomPlan);
+        helper.assertTrue((color & 0xFF00FF) == 0 && ((color >> 8) & 255) <= 240
+                        && ((color >> 8) & 255) % 10 == 0,
+                "An unnumbered color gets one seeded base-25 digit and leaves omitted channels at zero");
+        helper.assertValueEqual(AgeEnvironmentCompiler.skyColor(AgeGenerationPlan.load(randomPlan.save())), color,
+                "A random color digit must not change when an Age is reloaded");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void alignedMoonEclipsesSunAndDimsLight(GameTestHelper helper) {
+        AgeSkyProfile.Body sun = new AgeSkyProfile.Body(AgeSkyProfile.Kind.SUN,
+                0xCC8844, 1.0F, 0.0F, 1.0D, 0.0F, true);
+        AgeSkyProfile.Body moon = new AgeSkyProfile.Body(AgeSkyProfile.Kind.MOON,
+                0xFFFFFF, 1.0F, 0.0F, 1.0D, 0.0F, true);
+        AgeSkyProfile clear = new AgeSkyProfile(AgeSkyProfile.Style.OVERWORLD, 0x6688AA, List.of(sun));
+        AgeSkyProfile eclipse = new AgeSkyProfile(AgeSkyProfile.Style.OVERWORLD, 0x6688AA,
+                List.of(sun, moon));
+        helper.assertValueEqual(eclipse.eclipseAt(0.0D), 1.0F,
+                "Centered sun and moon must produce a full eclipse");
+        helper.assertTrue(eclipse.lightAt(0.0D) < clear.lightAt(0.0D),
+                "An eclipse must dim world skylight, not just the rendered sprites");
+        AgeSkyProfile separated = new AgeSkyProfile(AgeSkyProfile.Style.OVERWORLD, 0x6688AA,
+                List.of(sun, new AgeSkyProfile.Body(AgeSkyProfile.Kind.MOON,
+                        0xFFFFFF, 1.0F, 0.0F, 1.0D, 0.5F, true)));
+        helper.assertValueEqual(separated.eclipseAt(0.0D), 0.0F,
+                "A moon on the far side of the sky must not eclipse the sun");
+        AgeSkyProfile glowOnlyOverlap = new AgeSkyProfile(AgeSkyProfile.Style.OVERWORLD, 0x6688AA,
+                List.of(sun, new AgeSkyProfile.Body(AgeSkyProfile.Kind.MOON,
+                        0xFFFFFF, 1.0F, 0.0F, 1.0D, 0.04F, true)));
+        helper.assertValueEqual(glowOnlyOverlap.eclipseAt(0.0D), 0.0F,
+                "Overlapping glows must not count as an eclipse before the opaque discs touch");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void randomAndAuthoredCelestialsKeepIndependentOrbits(GameTestHelper helper) {
+        AgeTraits traits = AgeTraits.select(12345L);
+        AgeSkyProfile first = AgeSkyProfile.random(12345L, traits);
+        helper.assertValueEqual(first, AgeSkyProfile.random(12345L, traits),
+                "A random Age must recreate the same sky from its saved seed");
+        helper.assertTrue(first.bodies().stream().filter(body -> body.kind() == AgeSkyProfile.Kind.SUN).count() <= 10
+                        && first.bodies().stream().filter(body -> body.kind() == AgeSkyProfile.Kind.MOON).count() <= 10,
+                "Random Ages must obey the same celestial limits as authored Ages");
+        OrderedWriting writing = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(), page("terrain/standard"), page("sky/end"),
+                page("angle/east"), page("direction/counterclockwise"), page("number/24"), page("color/red"),
+                page("size/large"), page("period/half"), page("celestial/sun"),
+                page("direction/clockwise"), page("celestial/moon")));
+        AgeGenerationPlan plan = AgeGenerationPlan.compile(writing, 12345L, AgeGenerationProfiles.STANDARD,
+                traits, helper.getLevel().registryAccess());
+        AgeSkyProfile sky = AgeSkyProfile.compile(plan, AgeEnvironmentCompiler.apply(plan, traits));
+        helper.assertValueEqual(sky.bodies().size(), 2, "Both written celestial bodies must be retained");
+        helper.assertValueEqual(sky.bodies().getFirst().angle(), 90.0F,
+                "The first body's compass angle must be independent");
+        helper.assertFalse(sky.bodies().getFirst().clockwise(),
+                "The first body should move counterclockwise");
+        helper.assertTrue(sky.bodies().getLast().clockwise(),
+                "The second body should move clockwise");
+        helper.assertValueEqual(AgeSkyProfile.compile(AgeGenerationPlan.load(plan.save()), traits), sky,
+                "Body angle and direction must survive Age-plan serialization");
+        helper.succeed();
+    }
+
     @GameTest(template = "empty")
     public static void writtenEnvironmentPersistsAndPageFreeAgesStaySeeded(GameTestHelper helper) {
         OrderedWriting writing = new OrderedWriting(List.of(

src/main/java/net/dnorberg/rivencraft/client/BookReceptacleRenderer.java

@@ -0,0 +1,72 @@
+package net.dnorberg.rivencraft.client;
+
+import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.VertexConsumer;
+import com.mojang.math.Axis;
+import net.dnorberg.rivencraft.block.BookReceptacleBlock;
+import net.dnorberg.rivencraft.block.entity.BookReceptacleBlockEntity;
+import net.dnorberg.rivencraft.registry.ModBlocks;
+import net.dnorberg.rivencraft.registry.ModItems;
+import net.minecraft.client.model.BookModel;
+import net.minecraft.client.model.geom.ModelLayers;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
+import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
+import net.minecraft.core.Direction;
+import net.minecraft.resources.ResourceLocation;
+
+/** Legacy's almost-closed book, oriented to the receptacle's mounting face. */
+public final class BookReceptacleRenderer implements BlockEntityRenderer<BookReceptacleBlockEntity> {
+    private static final ResourceLocation LINKING_TEXTURE = ResourceLocation.fromNamespaceAndPath(
+            "rivencraft", "textures/entity/linking_book.png");
+    private static final ResourceLocation DESCRIPTIVE_TEXTURE = ResourceLocation.fromNamespaceAndPath(
+            "rivencraft", "textures/entity/descriptive_book.png");
+    private final BookModel model;
+
+    public BookReceptacleRenderer(BlockEntityRendererProvider.Context context) {
+        model = new BookModel(context.bakeLayer(ModelLayers.BOOK));
+    }
+
+    @Override
+    public void render(BookReceptacleBlockEntity receptacle, float partialTick, PoseStack poseStack,
+                       MultiBufferSource buffers, int packedLight, int packedOverlay) {
+        if (receptacle.getLevel() == null) return;
+        var state = receptacle.getLevel().getBlockState(receptacle.getBlockPos());
+        if (!state.is(ModBlocks.BOOK_RECEPTACLE.get())
+                || !state.getValue(BookReceptacleBlock.HAS_BOOK)
+                || receptacle.getBook().isEmpty()) return;
+
+        poseStack.pushPose();
+        poseStack.translate(0.5, 0.5, 0.5);
+        Direction facing = state.getValue(BookReceptacleBlock.FACING);
+        switch (facing) {
+            case UP -> {
+                // Rotate the whole assembled top-mounted receptacle/book pair
+                // around the block center, matching the x=90 block model.
+                poseStack.mulPose(Axis.ZP.rotationDegrees(180));
+                poseStack.mulPose(Axis.XP.rotationDegrees(-90));
+                poseStack.mulPose(Axis.YP.rotationDegrees(90));
+                // Preserve the local half-turn that seats the book in its slot.
+                poseStack.mulPose(Axis.ZP.rotationDegrees(180));
+            }
+            case DOWN -> {
+                // The ceiling-mounted model is the inverted top assembly.
+                poseStack.mulPose(Axis.XP.rotationDegrees(-90));
+                poseStack.mulPose(Axis.YP.rotationDegrees(90));
+                poseStack.mulPose(Axis.ZP.rotationDegrees(180));
+            }
+            case NORTH -> poseStack.mulPose(Axis.YP.rotationDegrees(-90));
+            case SOUTH -> poseStack.mulPose(Axis.YP.rotationDegrees(90));
+            case EAST -> poseStack.mulPose(Axis.YP.rotationDegrees(180));
+            case WEST -> { }
+        }
+        poseStack.scale(0.8F, 0.8F, 0.8F);
+        model.setupAnim(0.0F, 0.1F, 0.1F, 0.005F);
+        ResourceLocation texture = receptacle.getBook().is(ModItems.DESCRIPTIVE_BOOK.get())
+                ? DESCRIPTIVE_TEXTURE : LINKING_TEXTURE;
+        VertexConsumer vertices = buffers.getBuffer(RenderType.entitySolid(texture));
+        model.render(poseStack, vertices, packedLight, packedOverlay, -1);
+        poseStack.popPose();
+    }
+}

src/main/java/net/dnorberg/rivencraft/client/ClientAgeCelestialAngles.java

@@ -2,23 +2,58 @@ package net.dnorberg.rivencraft.client;
 
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
 import net.dnorberg.rivencraft.network.AgeCelestialAnglePayload;
 import net.minecraft.resources.ResourceKey;
 import net.minecraft.world.level.Level;
 import net.neoforged.neoforge.network.handling.IPayloadContext;
+import net.neoforged.neoforge.network.PacketDistributor;
+import net.dnorberg.rivencraft.network.RequestAgeSkyPayload;
 
 /** Client cache used by both the active world and remote preview renderers. */
 public final class ClientAgeCelestialAngles {
     private static final Map<ResourceKey<Level>, Float> ANGLES = new ConcurrentHashMap<>();
+    private static final Map<ResourceKey<Level>, AgeSkyProfile> SKIES = new ConcurrentHashMap<>();
+    private static final Map<ResourceKey<Level>, Long> LAST_REQUEST = new ConcurrentHashMap<>();
 
     private ClientAgeCelestialAngles() {
     }
 
     public static void handle(AgeCelestialAnglePayload payload, IPayloadContext context) {
         ANGLES.put(payload.dimension(), payload.angle());
+        SKIES.put(payload.dimension(), payload.sky());
+        LAST_REQUEST.remove(payload.dimension());
+    }
+
+    public static void requestIfMissing(ResourceKey<Level> dimension) {
+        if (!dimension.location().getNamespace().equals("rivencraft") || SKIES.containsKey(dimension)) return;
+        long now = System.nanoTime();
+        Long previous = LAST_REQUEST.putIfAbsent(dimension, now);
+        if (previous != null && now - previous < 2_000_000_000L) return;
+        LAST_REQUEST.put(dimension, now);
+        PacketDistributor.sendToServer(new RequestAgeSkyPayload(dimension));
+    }
+
+    public static void clear() {
+        ANGLES.clear();
+        SKIES.clear();
+        LAST_REQUEST.clear();
     }
 
     public static float get(ResourceKey<Level> dimension) {
         return ANGLES.getOrDefault(dimension, 0.0F);
     }
+
+    public static int skyColor(ResourceKey<Level> dimension) {
+        return sky(dimension).color();
+    }
+
+    public static boolean staticSky(ResourceKey<Level> dimension) {
+        return sky(dimension).style() == AgeSkyProfile.Style.STATIC;
+    }
+
+    public static AgeSkyProfile sky(ResourceKey<Level> dimension) {
+        return SKIES.getOrDefault(dimension,
+                new AgeSkyProfile(AgeSkyProfile.Style.INHERITED, -1, java.util.List.of()));
+    }
 }

src/main/java/net/dnorberg/rivencraft/client/ClientEvents.java

@@ -19,6 +19,12 @@ import net.neoforged.neoforge.common.NeoForge;
 import net.neoforged.neoforge.client.event.EntityRenderersEvent;
 import net.neoforged.neoforge.client.event.RegisterMenuScreensEvent;
 import net.neoforged.neoforge.client.event.RegisterClientReloadListenersEvent;
+import net.neoforged.neoforge.client.event.RegisterDimensionSpecialEffectsEvent;
+import net.neoforged.neoforge.client.event.RegisterColorHandlersEvent;
+import net.neoforged.neoforge.client.event.ClientPlayerNetworkEvent;
+import net.dnorberg.rivencraft.block.entity.CrystalPortalBlockEntity;
+import net.dnorberg.rivencraft.block.entity.BookReceptacleBlockEntity;
+import net.dnorberg.rivencraft.book.AgeEnvironmentCompiler;
 import net.neoforged.neoforge.client.extensions.common.IClientItemExtensions;
 import net.neoforged.neoforge.client.extensions.common.RegisterClientExtensionsEvent;
 import net.minecraft.client.renderer.BlockEntityWithoutLevelRenderer;
@@ -38,10 +44,28 @@ public final class ClientEvents {
     public static void registerRenderers(EntityRenderersEvent.RegisterRenderers event) {
         event.registerEntityRenderer(ModEntities.DROPPED_BOOK.get(), DroppedBookRenderer::new);
         event.registerBlockEntityRenderer(ModBlockEntities.BOOK_STAND.get(), BookStandRenderer::new);
+        event.registerBlockEntityRenderer(ModBlockEntities.BOOK_RECEPTACLE.get(), BookReceptacleRenderer::new);
         event.registerBlockEntityRenderer(ModBlockEntities.WRITING_DESK.get(), WritingDeskRenderer::new);
         event.registerBlockEntityRenderer(ModBlockEntities.STAR_FISSURE.get(), StarFissureRenderer::new);
     }
 
+    @SubscribeEvent
+    public static void registerSkyEffects(RegisterDimensionSpecialEffectsEvent event) {
+        event.register(AgeEnvironmentCompiler.CUSTOM_SKY_EFFECTS, new RivencraftSkyEffects());
+    }
+
+    @SubscribeEvent
+    public static void registerPortalColor(RegisterColorHandlersEvent.Block event) {
+        event.register((state, level, pos, tintIndex) -> {
+            if (level == null || pos == null || tintIndex != 0
+                    || !(level.getBlockEntity(pos) instanceof CrystalPortalBlockEntity portal)
+                    || portal.receptacle() == null
+                    || !(level.getBlockEntity(portal.receptacle()) instanceof BookReceptacleBlockEntity holder)
+                    || holder.destination() == null) return 0xFFFFFF;
+            return holder.skyColor();
+        }, ModBlocks.CRYSTAL_PORTAL.get());
+    }
+
     @SubscribeEvent
     public static void registerScreens(RegisterMenuScreensEvent event) {
         event.register(ModMenus.NOTEBOOK.get(), NotebookScreen::new);
@@ -98,6 +122,11 @@ public final class ClientEvents {
         NeoForge.EVENT_BUS.addListener(ClientBookExploreOverlay::onClientTickPost);
         NeoForge.EVENT_BUS.addListener(ClientBookExploreOverlay::onRenderGui);
         NeoForge.EVENT_BUS.addListener(ClientBookExploreOverlay::onMouseButton);
+        NeoForge.EVENT_BUS.addListener(ClientEvents::onLogout);
+    }
+
+    private static void onLogout(ClientPlayerNetworkEvent.LoggingOut event) {
+        ClientAgeCelestialAngles.clear();
     }
 
 }

src/main/java/net/dnorberg/rivencraft/client/RivencraftSkyEffects.java

@@ -0,0 +1,181 @@
+package net.dnorberg.rivencraft.client;
+
+import com.mojang.blaze3d.systems.RenderSystem;
+import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.vertex.BufferBuilder;
+import com.mojang.blaze3d.vertex.BufferUploader;
+import com.mojang.blaze3d.vertex.DefaultVertexFormat;
+import com.mojang.blaze3d.vertex.PoseStack;
+import com.mojang.blaze3d.vertex.Tesselator;
+import com.mojang.blaze3d.vertex.VertexFormat;
+import java.util.Random;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
+import net.minecraft.client.Camera;
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.client.renderer.DimensionSpecialEffects;
+import net.minecraft.client.renderer.FogRenderer;
+import net.minecraft.client.renderer.GameRenderer;
+import net.minecraft.world.phys.Vec3;
+import org.joml.Matrix4f;
+import com.mojang.math.Axis;
+import net.minecraft.resources.ResourceLocation;
+
+/** An authored sky can use vanilla celestial rendering or Legacy-style moving TV static. */
+public final class RivencraftSkyEffects extends DimensionSpecialEffects {
+    private static final int GRID = 16;
+    private static final int STATIC_GRID = 48;
+    private static final float RADIUS = 100.0F;
+    private static final ResourceLocation SUN = ResourceLocation.withDefaultNamespace("textures/environment/sun.png");
+    private static final ResourceLocation MOON = ResourceLocation.withDefaultNamespace("textures/environment/moon_phases.png");
+
+    public RivencraftSkyEffects() {
+        super(192.0F, true, SkyType.NORMAL, false, false);
+    }
+
+    @Override
+    public Vec3 getBrightnessDependentFogColor(Vec3 color, float brightness) {
+        return color.multiply(brightness * 0.94F + 0.06F,
+                brightness * 0.94F + 0.06F, brightness * 0.91F + 0.09F);
+    }
+
+    @Override
+    public boolean isFoggyAt(int x, int y) {
+        return false;
+    }
+
+    @Override
+    public boolean renderSky(ClientLevel level, int ticks, float partialTick, Matrix4f modelViewMatrix,
+                             Camera camera, Matrix4f projectionMatrix, boolean isFoggy, Runnable setupFog) {
+        AgeSkyProfile sky = ClientAgeCelestialAngles.sky(level.dimension());
+        if (sky.style() != AgeSkyProfile.Style.STATIC && sky.color() == -1 && sky.bodies().isEmpty()
+                && sky.style() != AgeSkyProfile.Style.NETHER && sky.style() != AgeSkyProfile.Style.END)
+            return false;
+        setupFog.run();
+        if (isFoggy) return true;
+
+        PoseStack pose = new PoseStack();
+        pose.mulPose(modelViewMatrix);
+        Matrix4f matrix = pose.last().pose();
+        Random random = new Random((level.getGameTime() + (long) ticks) / 2L);
+        int tint = sky.color();
+        if (tint == -1) tint = switch (sky.style()) {
+            case NETHER -> 0x6B2725;
+            case END -> 0x211835;
+            case STATIC -> 0x929292;
+            default -> level.getBiome(camera.getBlockPosition()).value().getSkyColor();
+        };
+        double time = level.getDayTime() + partialTick;
+        float eclipseShade = 1.0F - 0.65F * sky.eclipseAt(time);
+
+        RenderSystem.depthMask(false);
+        RenderSystem.disableCull();
+        RenderSystem.setShader(GameRenderer::getPositionColorShader);
+        RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1.0F);
+        FogRenderer.setupNoFog();
+        BufferBuilder vertices = Tesselator.getInstance().begin(
+                VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_COLOR);
+        int grid = sky.style() == AgeSkyProfile.Style.STATIC ? STATIC_GRID : GRID;
+        for (int axis = 0; axis < 3; axis++) {
+            for (int sign : new int[]{-1, 1}) {
+                for (int x = 0; x < grid; x++) {
+                    for (int y = 0; y < grid; y++) {
+                        int noise = sky.style() == AgeSkyProfile.Style.STATIC
+                                ? 65 + random.nextInt(160) : 255;
+                        int red = (int) (((tint >> 16) & 255) * noise / 255.0F * eclipseShade);
+                        int green = (int) (((tint >> 8) & 255) * noise / 255.0F * eclipseShade);
+                        int blue = (int) ((tint & 255) * noise / 255.0F * eclipseShade);
+                        int color = 0xFF000000 | red << 16 | green << 8 | blue;
+                        float left = -RADIUS + x * (2 * RADIUS / grid);
+                        float right = -RADIUS + (x + 1) * (2 * RADIUS / grid);
+                        float bottom = -RADIUS + y * (2 * RADIUS / grid);
+                        float top = -RADIUS + (y + 1) * (2 * RADIUS / grid);
+                        vertex(vertices, matrix, axis, sign, left, bottom, color);
+                        vertex(vertices, matrix, axis, sign, right, bottom, color);
+                        vertex(vertices, matrix, axis, sign, right, top, color);
+                        vertex(vertices, matrix, axis, sign, left, top, color);
+                    }
+                }
+            }
+        }
+        BufferUploader.drawWithShader(vertices.buildOrThrow());
+        if (!sky.bodies().isEmpty()) {
+            RenderSystem.enableBlend();
+            RenderSystem.defaultBlendFunc();
+            // Draw suns first so an aligned moon can pass visibly in front of them.
+            for (AgeSkyProfile.Body body : sky.bodies())
+                if (body.kind() == AgeSkyProfile.Kind.SUN) drawBody(pose, body, time, sky.eclipseFor(body, time));
+            for (AgeSkyProfile.Body body : sky.bodies())
+                if (body.kind() == AgeSkyProfile.Kind.MOON) drawBody(pose, body, time, sky.eclipseFor(body, time));
+            RenderSystem.disableBlend();
+        }
+        setupFog.run();
+        RenderSystem.enableCull();
+        RenderSystem.depthMask(true);
+        return true;
+    }
+
+    private static void drawBody(PoseStack pose, AgeSkyProfile.Body body, double time, float eclipse) {
+        pose.pushPose();
+        pose.mulPose(Axis.YP.rotationDegrees(body.angle()));
+        double orbit = body.period() == 0 ? body.phase()
+                : (body.clockwise() ? 1.0D : -1.0D) * time
+                        / (24000.0D * body.period()) + body.phase();
+        pose.mulPose(Axis.XP.rotationDegrees((float) (orbit * 360.0D)));
+        float size = (body.kind() == AgeSkyProfile.Kind.SUN ? 30.0F : 20.0F) * body.size();
+        int color = body.color();
+        float red = ((color >> 16) & 255) / 255.0F;
+        float green = ((color >> 8) & 255) / 255.0F;
+        float blue = (color & 255) / 255.0F;
+        if (body.kind() == AgeSkyProfile.Kind.MOON) {
+            red *= 1.0F - eclipse;
+            green *= 1.0F - eclipse;
+            blue *= 1.0F - eclipse;
+        } else {
+            float corona = (float) Math.pow(eclipse, 8.0D) * 0.8F;
+            red += (1.0F - red) * corona;
+            green += (1.0F - green) * corona;
+            blue += (1.0F - blue) * corona;
+        }
+        RenderSystem.setShader(GameRenderer::getPositionTexShader);
+        RenderSystem.setShaderTexture(0, body.kind() == AgeSkyProfile.Kind.SUN ? SUN : MOON);
+        // Vanilla's sun/moon atlases have opaque dark pixels around the bright center.
+        // Additive blending makes those pixels invisible while retaining the halo.
+        RenderSystem.blendFunc(GlStateManager.SourceFactor.SRC_ALPHA, GlStateManager.DestFactor.ONE);
+        RenderSystem.setShaderColor(red, green, blue,
+                body.kind() == AgeSkyProfile.Kind.SUN ? 0.84F : 0.88F + 0.12F * eclipse);
+        float uMax = body.kind() == AgeSkyProfile.Kind.SUN ? 1.0F : 0.25F;
+        float vMax = body.kind() == AgeSkyProfile.Kind.SUN ? 1.0F : 0.5F;
+        drawTexturedQuad(pose.last().pose(), -size, size, 0.0F, uMax, 0.0F, vMax);
+
+        // The 8x8 center of each 32x32 sprite is the actual body. Draw it last
+        // with ordinary alpha blending and full opacity so the sky and other
+        // celestial glows cannot show through it, including during an eclipse.
+        RenderSystem.defaultBlendFunc();
+        RenderSystem.setShaderColor(red, green, blue, 1.0F);
+        drawTexturedQuad(pose.last().pose(), -size * 0.25F, size * 0.25F,
+                uMax * 0.375F, uMax * 0.625F, vMax * 0.375F, vMax * 0.625F);
+        RenderSystem.setShaderColor(1.0F, 1.0F, 1.0F, 1.0F);
+        pose.popPose();
+    }
+
+    private static void drawTexturedQuad(Matrix4f matrix, float min, float max,
+                                         float uMin, float uMax, float vMin, float vMax) {
+        BufferBuilder vertices = Tesselator.getInstance().begin(VertexFormat.Mode.QUADS,
+                DefaultVertexFormat.POSITION_TEX);
+        vertices.addVertex(matrix, min, RADIUS - 1.0F, min).setUv(uMin, vMin);
+        vertices.addVertex(matrix, max, RADIUS - 1.0F, min).setUv(uMax, vMin);
+        vertices.addVertex(matrix, max, RADIUS - 1.0F, max).setUv(uMax, vMax);
+        vertices.addVertex(matrix, min, RADIUS - 1.0F, max).setUv(uMin, vMax);
+        BufferUploader.drawWithShader(vertices.buildOrThrow());
+    }
+
+    private static void vertex(BufferBuilder vertices, Matrix4f matrix, int axis, int sign,
+                               float x, float y, int color) {
+        float fixed = sign * RADIUS;
+        switch (axis) {
+            case 0 -> vertices.addVertex(matrix, fixed, x, y).setColor(color);
+            case 1 -> vertices.addVertex(matrix, x, fixed, y).setColor(color);
+            default -> vertices.addVertex(matrix, x, y, fixed).setColor(color);
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/client/SymbolPageTextures.java

@@ -138,6 +138,17 @@ public final class SymbolPageTextures {
                         y * base.getHeight() / SIZE));
             }
         }
+        String numberPath = id.getPath().startsWith("number/")
+                ? id.getPath().substring("number/".length()) : "";
+        if (id.getNamespace().equals(Rivencraft.MOD_ID)
+                && numberPath.matches("(?:[0-9]|1[0-9]|2[0-4])")) {
+            int digit = Integer.parseInt(numberPath);
+            int glyphSize = item ? GLYPH * ITEM_SYMBOL_SIZE / ICON_SIZE : GLYPH;
+            int origin = item ? scaleForItem(38) : 38;
+            for (int component : SymbolNumerals.componentsForDigit(digit))
+                blendComponent(image, component, origin, origin, glyphSize);
+            return image;
+        }
         String[] words = poem.isBlank() ? generatedWords(id) : poem.split(" ");
         int[] offsetsX = {38, 77, 38, 0};
         int[] offsetsY = {0, 38, 77, 38};
@@ -146,18 +157,22 @@ public final class SymbolPageTextures {
             int originX = item ? scaleForItem(offsetsX[word]) : offsetsX[word];
             int originY = item ? scaleForItem(offsetsY[word]) : offsetsY[word];
             for (int component : glyphs(words[word])) {
-                for (int y = 0; y < glyphSize; y++) for (int x = 0; x < glyphSize; x++) {
-                    int pixel = components.getPixelRGBA((component % 8) * 64 + x * 64 / glyphSize,
-                            (component / 8) * 64 + y * 64 / glyphSize);
-                    int alpha = pixel >>> 24;
-                    if (alpha != 0) image.blendPixel(originX + x, originY + y,
-                            (alpha << 24) | 0x001A212B);
-                }
+                blendComponent(image, component, originX, originY, glyphSize);
             }
         }
         return image;
     }
 
+    private static void blendComponent(NativeImage image, int component, int originX, int originY, int glyphSize) {
+        for (int y = 0; y < glyphSize; y++) for (int x = 0; x < glyphSize; x++) {
+            int pixel = components.getPixelRGBA((component % 8) * 64 + x * 64 / glyphSize,
+                    (component / 8) * 64 + y * 64 / glyphSize);
+            int alpha = pixel >>> 24;
+            if (alpha != 0) image.blendPixel(originX + x, originY + y,
+                    (alpha << 24) | 0x001A212B);
+        }
+    }
+
     private static int scaleForItem(int coordinate) {
         return SIZE / 2 + Math.round((coordinate - SIZE / 2F) * ITEM_SYMBOL_SIZE / ICON_SIZE);
     }

src/main/java/net/dnorberg/rivencraft/compat/RuinsCompatibility.java

@@ -0,0 +1,77 @@
+package net.dnorberg.rivencraft.compat;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import net.dnorberg.rivencraft.book.AgeDefinition;
+import net.dnorberg.rivencraft.book.AgeFeatureSelection;
+import net.minecraft.resources.ResourceLocation;
+import net.neoforged.fml.ModList;
+
+/** Small optional bridge between frozen Age pages and Ruins' dimension gate. */
+public final class RuinsCompatibility {
+    private static final Set<ResourceLocation> KNOWN_AGES = ConcurrentHashMap.newKeySet();
+    private static final Map<ResourceLocation, Map<ResourceLocation, Integer>> AUTHORED_TEMPLATES =
+            new ConcurrentHashMap<>();
+
+    private RuinsCompatibility() {}
+
+    public static void register() {
+        if (ModList.get().isLoaded("ruins")) RuinsEventAdapter.register();
+    }
+
+    public static void registerAge(AgeDefinition age) {
+        if (!ModList.get().isLoaded("ruins")) return;
+        KNOWN_AGES.add(age.dimensionId());
+        List<AgeFeatureSelection.Choice> choices = age.plan() == null
+                ? age.randomFeatures() : AgeFeatureSelection.resolved(age.plan());
+        Map<ResourceLocation, Integer> selected = templateCounts(choices);
+        if (!selected.isEmpty()) {
+            AUTHORED_TEMPLATES.put(age.dimensionId(), selected);
+        } else {
+            AUTHORED_TEMPLATES.remove(age.dimensionId());
+        }
+    }
+
+    /** Called only by the optional Ruins FileHandler mixin. */
+    public static boolean allowsAge(ResourceLocation dimension) {
+        return AUTHORED_TEMPLATES.containsKey(dimension);
+    }
+
+    public static boolean isKnownAge(ResourceLocation dimension) {
+        return KNOWN_AGES.contains(dimension);
+    }
+
+    public static boolean permits(ResourceLocation dimension, ResourceLocation template) {
+        return templateCount(dimension, template) > 0;
+    }
+
+    public static int templateCount(ResourceLocation dimension, ResourceLocation template) {
+        return AUTHORED_TEMPLATES.getOrDefault(dimension, Map.of()).getOrDefault(template, 0);
+    }
+
+    /** Extra pages increase attempts, without making distinct template choices denser. */
+    public static int attemptsPerChunk(ResourceLocation dimension, int configuredAttempts) {
+        return attemptsPerChunk(configuredAttempts, AUTHORED_TEMPLATES.get(dimension));
+    }
+
+    static int attemptsPerChunk(int configuredAttempts, Map<ResourceLocation, Integer> counts) {
+        if (counts == null || counts.isEmpty()) return configuredAttempts;
+        int duplicates = counts.values().stream().mapToInt(count -> count - 1).sum();
+        return (int) Math.min(Math.max(configuredAttempts, 32L), (long) configuredAttempts + duplicates);
+    }
+
+    static Map<ResourceLocation, Integer> templateCounts(List<AgeFeatureSelection.Choice> choices) {
+        Map<ResourceLocation, Integer> counts = new java.util.HashMap<>();
+        for (AgeFeatureSelection.Choice choice : choices) {
+            if (RuinsTemplatePages.contains(choice.id())) counts.merge(choice.id(), 1, Integer::sum);
+        }
+        return Map.copyOf(counts);
+    }
+
+    public static void onServerStopping() {
+        KNOWN_AGES.clear();
+        AUTHORED_TEMPLATES.clear();
+    }
+}

src/main/java/net/dnorberg/rivencraft/compat/RuinsCompatibilityGameTests.java

@@ -0,0 +1,123 @@
+package net.dnorberg.rivencraft.compat;
+
+import net.dnorberg.rivencraft.item.PageItem;
+import net.dnorberg.rivencraft.book.AgeFeatureSelection;
+import net.dnorberg.rivencraft.book.AgeReference;
+import net.dnorberg.rivencraft.book.AgeRegistrySavedData;
+import net.dnorberg.rivencraft.writing.OrderedWriting;
+import net.dnorberg.rivencraft.writing.WritingEntry;
+import java.util.List;
+import java.util.Map;
+import java.util.Optional;
+import java.util.UUID;
+import java.nio.file.Files;
+import net.neoforged.fml.loading.FMLPaths;
+import net.dnorberg.rivencraft.writing.SymbolCatalog;
+import net.dnorberg.rivencraft.writing.SymbolReference;
+import net.minecraft.gametest.framework.GameTest;
+import net.minecraft.gametest.framework.GameTestHelper;
+import net.neoforged.fml.ModList;
+import net.neoforged.neoforge.gametest.GameTestHolder;
+import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
+
+/** Each discoverable Ruins template must have an authorable page, or none do. */
+@GameTestHolder("rivencraft")
+@PrefixGameTestTemplate(false)
+public final class RuinsCompatibilityGameTests {
+    private RuinsCompatibilityGameTests() {}
+
+    @GameTest(template = "empty")
+    public static void ruinsPagesMatchInstalledTemplates(GameTestHelper helper) {
+        var templates = RuinsTemplatePages.templates();
+        if (!ModList.get().isLoaded("ruins")) {
+            helper.assertTrue(templates.isEmpty(), "Ruins pages must be absent without the optional mod");
+        } else {
+            var creative = PageItem.creativeSymbolPages(helper.getLevel().registryAccess(),
+                    RuinsTemplatePages.CATEGORY);
+            helper.assertValueEqual(creative.size(), templates.size(),
+                    "Creative and JEI must expose exactly one page per Ruins template");
+            for (String name : templates) {
+                var id = RuinsTemplatePages.symbolId(name);
+                helper.assertTrue(SymbolCatalog.isKnown(new SymbolReference(id)),
+                        "Ruins template " + name + " must be authorable");
+                helper.assertTrue(PageItem.isUsableWriting(PageItem.createCreativeRuinsPage(name)),
+                        "Ruins template " + name + " needs a usable page");
+            }
+        }
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void duplicatePagesRetainTheirCount(GameTestHelper helper) {
+        if (RuinsTemplatePages.templates().isEmpty()) {
+            helper.succeed();
+            return;
+        }
+        var template = RuinsTemplatePages.symbolId(RuinsTemplatePages.templates().getFirst());
+        var counts = RuinsCompatibility.templateCounts(List.of(
+                new AgeFeatureSelection.Choice(template, Optional.empty()),
+                new AgeFeatureSelection.Choice(template, Optional.empty()),
+                new AgeFeatureSelection.Choice(template, Optional.empty())));
+        helper.assertValueEqual(counts.get(template), 3,
+                "Three authored Ruins pages must triple that template's relative selection weight");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void duplicatePagesIncreaseAttemptsWithinBudget(GameTestHelper helper) {
+        var first = RuinsTemplatePages.symbolId("First.tml");
+        var second = RuinsTemplatePages.symbolId("Second.tml");
+        helper.assertValueEqual(RuinsCompatibility.attemptsPerChunk(6, Map.of(first, 1)), 6,
+                "One Ruins page must retain the configured attempt count");
+        helper.assertValueEqual(RuinsCompatibility.attemptsPerChunk(6, Map.of(first, 3, second, 1)), 8,
+                "Only duplicate pages must add one attempt each");
+        helper.assertValueEqual(RuinsCompatibility.attemptsPerChunk(6, Map.of(first, 50)), 32,
+                "Duplicate pages must not exceed the per-chunk attempt budget");
+        helper.assertValueEqual(RuinsCompatibility.attemptsPerChunk(40, Map.of(first, 2)), 40,
+                "The budget must not lower an intentionally higher Ruins configuration");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void authoredTemplateBypassesOverworldOnlyGate(GameTestHelper helper) throws Exception {
+        if (!ModList.get().isLoaded("ruins")) {
+            helper.succeed();
+            return;
+        }
+        String name = "tikihead1.tml";
+        var path = FMLPaths.GAMEDIR.get().resolve("config/ruins_config/generic").resolve(name);
+        if (!Files.exists(path) || !RuinsTemplatePages.contains(RuinsTemplatePages.symbolId(name))) {
+            helper.succeed(); // Custom Ruins packs need not include the bundled Tiki Head.
+            return;
+        }
+        var writing = new OrderedWriting(List.of(
+                WritingEntry.linkPanel(),
+                WritingEntry.symbol(new SymbolReference(net.minecraft.resources.ResourceLocation.parse(
+                        "rivencraft:terrain/standard"))),
+                WritingEntry.symbol(new SymbolReference(net.minecraft.resources.ResourceLocation.parse(
+                        "rivencraft:biome/plains"))),
+                WritingEntry.symbol(new SymbolReference(net.minecraft.resources.ResourceLocation.parse(
+                        "rivencraft:biome/single"))),
+                WritingEntry.symbol(new SymbolReference(RuinsTemplatePages.symbolId(name)))));
+        var age = AgeRegistrySavedData.resolveOrCreate(helper.getLevel(),
+                new AgeReference(UUID.randomUUID(), "Ruins Tiki Gate"), writing);
+        RuinsCompatibility.registerAge(age);
+        var ruinsClass = Class.forName("atomicstryker.ruins.common.RuinsMod");
+        Object ruins = ruinsClass.getMethod("getInstance").invoke(null);
+        var currentLevel = ruinsClass.getDeclaredField("lastLoadedLevel");
+        currentLevel.setAccessible(true);
+        Object previousLevel = currentLevel.get(ruins);
+        var templateClass = Class.forName("atomicstryker.ruins.common.RuinTemplate");
+        try {
+            currentLevel.set(ruins, helper.getLevel());
+            Object template = templateClass.getConstructor(String.class, String.class)
+                    .newInstance(path.toString(), name);
+            boolean accepted = (boolean) templateClass.getMethod("acceptsDimension", String.class)
+                    .invoke(template, age.dimensionId().getPath());
+            helper.assertTrue(accepted, "The authored Tiki Head must load despite dimensionsToSpawnIn=overworld");
+        } finally {
+            currentLevel.set(ruins, previousLevel);
+        }
+        helper.succeed();
+    }
+}

src/main/java/net/dnorberg/rivencraft/compat/RuinsEventAdapter.java

@@ -0,0 +1,53 @@
+package net.dnorberg.rivencraft.compat;
+
+import atomicstryker.ruins.common.EventRuinTemplateSpawn;
+import atomicstryker.ruins.common.RuinTemplate;
+import java.util.Collection;
+import java.util.Comparator;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.util.RandomSource;
+import net.neoforged.neoforge.common.NeoForge;
+
+/** Loaded only when Ruins is present. Its pre-spawn event can veto exact templates. */
+public final class RuinsEventAdapter {
+    private RuinsEventAdapter() {}
+
+    static void register() {
+        NeoForge.EVENT_BUS.addListener(RuinsEventAdapter::onTemplateSpawn);
+    }
+
+    private static void onTemplateSpawn(EventRuinTemplateSpawn event) {
+        if (!event.isPrePhase || event.testingRuin
+                || !(event.getLevel() instanceof ServerLevel level)
+                || !RuinsCompatibility.isKnownAge(level.dimension().location())) return;
+
+        var template = RuinsTemplatePages.featureId(event.template.getName());
+        if (!RuinsTemplatePages.contains(template)
+                || !RuinsCompatibility.permits(level.dimension().location(), template)) event.setCancelled(true);
+    }
+
+    /** Preserve Ruins' weights and multiply each by its authored page count. */
+    public static Object chooseTemplate(net.minecraft.resources.ResourceLocation dimension,
+                                        Collection<?> pool, RandomSource random) {
+        if (pool == null || pool.isEmpty()) return null;
+        var candidates = pool.stream().filter(RuinTemplate.class::isInstance)
+                .map(RuinTemplate.class::cast)
+                .filter(template -> RuinsCompatibility.permits(dimension,
+                        RuinsTemplatePages.featureId(template.getName())))
+                .sorted(Comparator.comparing(RuinTemplate::getName)).toList();
+        double total = candidates.stream().mapToDouble(template -> authoredWeight(dimension, template)).sum();
+        if (total <= 0.0) return null;
+        double roll = random.nextDouble() * total;
+        for (RuinTemplate candidate : candidates) {
+            roll -= authoredWeight(dimension, candidate);
+            if (roll < 0.0) return candidate;
+        }
+        return candidates.getLast();
+    }
+
+    private static double authoredWeight(net.minecraft.resources.ResourceLocation dimension,
+                                         RuinTemplate template) {
+        return Math.max(0.0, template.getWeight()) * RuinsCompatibility.templateCount(dimension,
+                RuinsTemplatePages.featureId(template.getName()));
+    }
+}

src/main/java/net/dnorberg/rivencraft/compat/RuinsTemplatePages.java

@@ -0,0 +1,162 @@
+package net.dnorberg.rivencraft.compat;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.charset.StandardCharsets;
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.HexFormat;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Optional;
+import java.util.Set;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.writing.SymbolDefinition;
+import net.dnorberg.rivencraft.writing.SymbolSemantics;
+import net.minecraft.resources.ResourceLocation;
+import net.neoforged.fml.ModList;
+import net.neoforged.fml.loading.FMLPaths;
+
+/** Discovers Ruins' template filenames without making its jar mandatory. */
+public final class RuinsTemplatePages {
+    public static final ResourceLocation CATEGORY = ResourceLocation.fromNamespaceAndPath(
+            Rivencraft.MOD_ID, "ruins");
+    private static final String PREFIX = "ruins/";
+    private static volatile Map<ResourceLocation, String> names = Map.of();
+    private static volatile boolean initialized;
+
+    private RuinsTemplatePages() {}
+
+    public static void refresh() {
+        if (!ModList.get().isLoaded("ruins")) {
+            names = Map.of();
+            initialized = true;
+            return;
+        }
+        Map<ResourceLocation, String> discovered = new HashMap<>();
+        Map<String, String> sources = new HashMap<>();
+        Set<String> duplicateNames = new HashSet<>();
+        // Ruins itself reads <gameDir>/config/ruins_config, not NeoForge's
+        // overrideable CONFIGDIR; mirror its active folder exactly.
+        Path configured = FMLPaths.GAMEDIR.get().resolve("config/ruins_config");
+        if (Files.isDirectory(configured)) {
+            try (var paths = Files.walk(configured)) {
+                paths.filter(Files::isRegularFile)
+                        .filter(path -> configured.relativize(path).getNameCount() == 2)
+                        .filter(path -> isTemplate(path.getFileName().toString()))
+                        .sorted().forEach(path -> add(discovered, sources, duplicateNames,
+                                path.getFileName().toString(), configured.relativize(path).toString()));
+            } catch (IOException exception) {
+                Rivencraft.LOGGER.warn("Could not read Ruins templates from {}", configured, exception);
+            }
+        }
+        // Ruins extracts this archive on first launch. It also supplies the creative
+        // pages before extraction has completed on a fresh installation.
+        if (discovered.isEmpty() && !Files.isDirectory(configured)) {
+            try (InputStream stream = RuinsTemplatePages.class.getClassLoader()
+                    .getResourceAsStream("assets/ruins_config.zip")) {
+                if (stream != null) {
+                    try (ZipInputStream zip = new ZipInputStream(stream)) {
+                        ZipEntry entry;
+                        while ((entry = zip.getNextEntry()) != null) {
+                            if (!entry.isDirectory()) {
+                                String name = entry.getName();
+                                name = name.substring(name.lastIndexOf('/') + 1);
+                                if (isTemplate(name)) add(discovered, sources, duplicateNames,
+                                        name, entry.getName());
+                            }
+                        }
+                    }
+                }
+            } catch (IOException exception) {
+                Rivencraft.LOGGER.warn("Could not read bundled Ruins templates", exception);
+            }
+        }
+        // Ruins' spawn event exposes only the basename. If two directories use
+        // that basename, Rivencraft cannot identify which structure was chosen.
+        // Disable the bridge instead of advertising pages with ambiguous effects.
+        if (!duplicateNames.isEmpty()) {
+            Rivencraft.LOGGER.error("Ruins compatibility disabled: duplicate template names {}. "
+                    + "Give every .tml file a unique basename.", duplicateNames);
+            names = Map.of();
+            initialized = true;
+            return;
+        }
+        names = Map.copyOf(discovered);
+        initialized = true;
+    }
+
+    public static List<String> templates() {
+        if (!initialized) refresh();
+        List<String> templates = new ArrayList<>(names.values());
+        templates.sort(Comparator.comparing(String::toLowerCase));
+        return List.copyOf(templates);
+    }
+
+    public static boolean isSymbol(ResourceLocation id) {
+        return id.getNamespace().equals(Rivencraft.MOD_ID) && id.getPath().startsWith(PREFIX);
+    }
+
+    public static boolean contains(ResourceLocation id) {
+        return isSymbol(id) && names.containsKey(id);
+    }
+
+    public static ResourceLocation symbolId(String templateName) {
+        if (templateName.isBlank()) throw new IllegalArgumentException("Ruins template has no usable name");
+        // Hex is reversible and collision-free even for case-sensitive or Unicode
+        // filenames; normalizing to lowercase would merge distinct templates.
+        String key = HexFormat.of().formatHex(templateName.getBytes(StandardCharsets.UTF_8));
+        return ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, PREFIX + "t_" + key);
+    }
+
+    public static ResourceLocation featureId(String templateName) {
+        return symbolId(templateName);
+    }
+
+    public static String fallbackName(ResourceLocation symbolId) {
+        String encoded = symbolId.getPath().substring(PREFIX.length());
+        if (!encoded.startsWith("t_")) return encoded + " Ruin";
+        String name;
+        try {
+            name = new String(HexFormat.of().parseHex(encoded.substring(2)), StandardCharsets.UTF_8);
+        } catch (IllegalArgumentException exception) {
+            name = encoded;
+        }
+        return stripExtension(name).replace('_', ' ') + " Ruin";
+    }
+
+    public static SymbolDefinition definition(String templateName) {
+        ResourceLocation id = featureId(templateName);
+        return new SymbolDefinition(SymbolDefinition.CURRENT_SCHEMA_VERSION,
+                "symbol.rivencraft.ruins.template", "symbol.rivencraft.ruins.description",
+                CATEGORY, Optional.of(new SymbolSemantics(SymbolSemantics.Role.FEATURE,
+                new SymbolSemantics.ResourceValue(id))), "");
+    }
+
+    private static boolean isTemplate(String name) {
+        return name.toLowerCase(Locale.ROOT).endsWith(".tml");
+    }
+
+    private static String stripExtension(String name) {
+        return isTemplate(name) ? name.substring(0, name.length() - 4) : name;
+    }
+
+    private static void add(Map<ResourceLocation, String> templates, Map<String, String> sources,
+                            Set<String> duplicateNames, String name, String source) {
+        String previousSource = sources.putIfAbsent(name, source);
+        if (previousSource != null && !previousSource.equals(source)) duplicateNames.add(name);
+        ResourceLocation id = symbolId(name);
+        String previous = templates.putIfAbsent(id, name);
+        if (previous != null && !previous.equals(name)) {
+            Rivencraft.LOGGER.warn("Ruins templates {} and {} share page ID {}; using {}",
+                    previous, name, id, previous);
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/event/AgeCelestialAngleSync.java

@@ -3,6 +3,7 @@ package net.dnorberg.rivencraft.event;
 import net.dnorberg.rivencraft.book.AgeDefinition;
 import net.dnorberg.rivencraft.book.AgeDimensionService;
 import net.dnorberg.rivencraft.book.AgeRegistrySavedData;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
 import net.dnorberg.rivencraft.network.AgeCelestialAnglePayload;
 import net.minecraft.server.level.ServerPlayer;
 import net.neoforged.neoforge.event.entity.player.PlayerEvent;
@@ -34,10 +35,10 @@ public final class AgeCelestialAngleSync {
     }
 
     public static void send(ServerPlayer player, AgeDefinition age) {
-        if (!NetworkRegistry.hasChannel(player.connection, AgeCelestialAnglePayload.TYPE.id())) {
-            return;
-        }
+        // GameTest mock players (and clients without this channel) cannot receive this payload.
+        if (!NetworkRegistry.hasChannel(player.connection, AgeCelestialAnglePayload.TYPE.id())) return;
         PacketDistributor.sendToPlayer(player, new AgeCelestialAnglePayload(
-                AgeDimensionService.dimensionKey(age), age.traits().celestialAngle()));
+                AgeDimensionService.dimensionKey(age), age.traits().celestialAngle(),
+                AgeSkyProfile.forAge(age)));
     }
 }

src/main/java/net/dnorberg/rivencraft/gametest/CrystalPortalGameTests.java

@@ -6,6 +6,9 @@ import net.dnorberg.rivencraft.block.CrystalPortalBlock;
 import net.dnorberg.rivencraft.block.entity.BookReceptacleBlockEntity;
 import net.dnorberg.rivencraft.block.entity.CrystalPortalBlockEntity;
 import net.dnorberg.rivencraft.book.LinkTarget;
+import net.dnorberg.rivencraft.book.LinkProperties;
+import net.dnorberg.rivencraft.book.LinkingService;
+import net.dnorberg.rivencraft.registry.ModDataComponents;
 import net.dnorberg.rivencraft.portal.CrystalPortalNetwork;
 import net.dnorberg.rivencraft.portal.CrystalPortalSurfaces;
 import net.dnorberg.rivencraft.portal.PortalTravelCooldown;
@@ -19,7 +22,11 @@ import net.minecraft.gametest.framework.GameTestHelper;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.item.context.BlockPlaceContext;
 import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.phys.BlockHitResult;
+import net.minecraft.world.phys.Vec3;
 import net.neoforged.neoforge.gametest.GameTestHolder;
 import net.neoforged.neoforge.gametest.PrefixGameTestTemplate;
 
@@ -46,6 +53,8 @@ public final class CrystalPortalGameTests {
         helper.assertTrue(plan.valid(), "A closed crystal frame must form a portal");
         BookReceptacleBlockEntity holder = (BookReceptacleBlockEntity) level.getBlockEntity(holderPos);
         holder.setBook(new ItemStack(ModItems.LINKING_BOOK.get()));
+        helper.assertTrue(level.getBlockState(holderPos).getValue(BookReceptacleBlock.HAS_BOOK),
+                "An occupied receptacle must expose its book state to client renderers");
         LinkTarget destination = new LinkTarget(GlobalPos.of(level.dimension(), centerTarget(helper)), 0, 0);
         holder.setDestination(destination);
         BookReceptacleBlockEntity restored = new BookReceptacleBlockEntity(holderPos, holder.getBlockState());
@@ -82,6 +91,12 @@ public final class CrystalPortalGameTests {
                 "A north/south opening must only show its two player-facing sides");
         CrystalPortalNetwork.shutdown(level, holderPos);
         helper.assertTrue(level.getBlockState(center).isAir(), "Removing the book must release the portal");
+        helper.assertTrue(holder.takeBook().is(ModItems.LINKING_BOOK.get()),
+                "Removing the book must return the stored item");
+        helper.assertTrue(!level.getBlockState(holderPos).getValue(BookReceptacleBlock.HAS_BOOK),
+                "Removing the book must clear the client-visible model state");
+        helper.assertTrue(!holder.getUpdateTag(level.registryAccess()).contains("Book"),
+                "The block-entity update must also clear the old client-side book stack");
         helper.succeed();
     }
 
@@ -154,13 +169,54 @@ public final class CrystalPortalGameTests {
         BlockPos holderPos = helper.absolutePos(new BlockPos(0, 2, 1));
         level.setBlock(holderPos, ModBlocks.BOOK_RECEPTACLE.get().defaultBlockState()
                 .setValue(BookReceptacleBlock.FACING, Direction.UP), 3);
-        ((BookReceptacleBlockEntity) level.getBlockEntity(holderPos))
-                .setBook(new ItemStack(ModItems.LINKING_BOOK.get()));
+        LinkTarget destination = new LinkTarget(GlobalPos.of(level.dimension(), centerTarget(helper)), 0, 0);
+        ItemStack book = new ItemStack(ModItems.LINKING_BOOK.get());
+        book.set(ModDataComponents.LINK_TARGET.get(), destination);
+        BookReceptacleBlockEntity holder = (BookReceptacleBlockEntity) level.getBlockEntity(holderPos);
+        holder.setBook(book);
+        holder.setDestination(destination);
         helper.assertTrue(CrystalPortalNetwork.activate(level, holderPos, planLoaded(level, holderPos)),
                 "The horizontal crystal opening must activate");
         helper.assertValueEqual(level.getBlockState(helper.absolutePos(new BlockPos(1, 1, 1)))
                 .getValue(CrystalPortalBlock.AXIS), Direction.Axis.Y,
                 "The fallback surface must face up and down");
+        helper.assertValueEqual(CrystalPortalSurfaces.group(level, planLoaded(level, holderPos)).getFirst().normal(),
+                Direction.UP, "The horizontal opening must provide an upward-facing destination view");
+        var player = helper.makeMockServerPlayerInLevel();
+        helper.assertValueEqual(LinkingService.travelPortal(player, destination, LinkProperties.NONE),
+                LinkingService.LinkResult.INTRA_LINKING_REQUIRED,
+                "A normal book may show a portal but must not link within its own dimension");
+        helper.assertTrue(level.getBlockState(helper.absolutePos(new BlockPos(1, 1, 1)))
+                        .is(ModBlocks.CRYSTAL_PORTAL.get()) && !holder.getBook().isEmpty(),
+                "Rejected intra-link travel must leave the visual portal and its book intact");
+        helper.succeed();
+    }
+
+    @GameTest(template = "empty")
+    public static void undersideReceptaclePlacesAndActivatesHorizontalFrame(GameTestHelper helper) {
+        var level = helper.getLevel();
+        for (int x = 0; x < 3; x++) for (int z = 0; z < 3; z++) {
+            level.setBlock(helper.absolutePos(new BlockPos(x, 2, z)),
+                    x == 1 && z == 1 ? Blocks.AIR.defaultBlockState()
+                            : ModBlocks.CRYSTAL_BLOCK.get().defaultBlockState(), 3);
+        }
+        BlockPos support = helper.absolutePos(new BlockPos(0, 2, 1));
+        BlockPos holderPos = support.below();
+        BlockPlaceContext context = new BlockPlaceContext(level, null, InteractionHand.MAIN_HAND,
+                new ItemStack(ModItems.BOOK_RECEPTACLE.get()),
+                new BlockHitResult(Vec3.atCenterOf(support).add(0, -0.5, 0),
+                        Direction.DOWN, support, false));
+        var placed = ModBlocks.BOOK_RECEPTACLE.get().getStateForPlacement(context);
+        helper.assertTrue(placed != null && placed.getValue(BookReceptacleBlock.FACING) == Direction.DOWN,
+                "Clicking the underside of a Crystal Block must place a downward-facing receptacle");
+        level.setBlock(holderPos, placed, 3);
+        ((BookReceptacleBlockEntity) level.getBlockEntity(holderPos))
+                .setBook(new ItemStack(ModItems.LINKING_BOOK.get()));
+        helper.assertTrue(CrystalPortalNetwork.activate(level, holderPos, planLoaded(level, holderPos)),
+                "A ceiling-mounted receptacle must activate its horizontal crystal frame");
+        helper.assertValueEqual(level.getBlockState(helper.absolutePos(new BlockPos(1, 2, 1)))
+                .getValue(CrystalPortalBlock.AXIS), Direction.Axis.Y,
+                "The underside-mounted portal surface remains horizontal");
         helper.succeed();
     }
 

src/main/java/net/dnorberg/rivencraft/item/PageItem.java

@@ -11,6 +11,7 @@ import java.util.ArrayList;
 import java.util.LinkedHashSet;
 import java.util.Set;
 import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.compat.RuinsTemplatePages;
 import net.dnorberg.rivencraft.book.AgeBiomeSelection;
 import net.dnorberg.rivencraft.book.LinkProperties;
 import net.dnorberg.rivencraft.compat.TerraBlenderBiomes;
@@ -71,6 +72,7 @@ public final class PageItem extends Item {
         categories.add(BlockSymbolPages.CATEGORY);
         categories.add(BlockSymbolPages.FLUID_CATEGORY);
         categories.add(CAVE_BIOME_CATEGORY);
+        if (!RuinsTemplatePages.templates().isEmpty()) categories.add(RuinsTemplatePages.CATEGORY);
         return List.copyOf(categories);
     }
 
@@ -78,6 +80,11 @@ public final class PageItem extends Item {
         if (category.equals(CAVE_BIOME_CATEGORY)) {
             return createCreativeBiomePage(ResourceLocation.withDefaultNamespace("lush_caves"));
         }
+        if (category.equals(RuinsTemplatePages.CATEGORY)) {
+            return RuinsTemplatePages.templates().stream().findFirst()
+                    .map(PageItem::createCreativeRuinsPage)
+                    .orElseGet(() -> createBundledCreativePage("feature/villages"));
+        }
         if (category.equals(BlockSymbolPages.CATEGORY) || category.equals(BlockSymbolPages.FLUID_CATEGORY)) {
             return createCreativeBlockPage(ResourceLocation.withDefaultNamespace(
                     category.equals(BlockSymbolPages.FLUID_CATEGORY) ? "water" : "stone"));
@@ -93,6 +100,7 @@ public final class PageItem extends Item {
     public static List<ItemStack> creativeSymbolPages(HolderLookup.Provider registries) {
         List<ItemStack> pages = creativeBundledAndBiomePages(registries);
         BlockSymbolPages.availableBlocks().forEach(id -> pages.add(createCreativeBlockPage(id)));
+        RuinsTemplatePages.templates().forEach(name -> pages.add(createCreativeRuinsPage(name)));
         return List.copyOf(pages);
     }
 
@@ -115,6 +123,9 @@ public final class PageItem extends Item {
             return BlockSymbolPages.availableBlocks(category).stream()
                     .map(PageItem::createCreativeBlockPage).toList();
         }
+        if (category.equals(RuinsTemplatePages.CATEGORY)) {
+            return RuinsTemplatePages.templates().stream().map(PageItem::createCreativeRuinsPage).toList();
+        }
         Set<ResourceLocation> caveBiomes = category.equals(BIOME_CATEGORY) || category.equals(CAVE_BIOME_CATEGORY)
                 ? caveBiomeIds(registries) : Set.of();
         return creativeBundledAndBiomePages(registries).stream()
@@ -180,6 +191,14 @@ public final class PageItem extends Item {
         return page;
     }
 
+    public static ItemStack createCreativeRuinsPage(String templateName) {
+        var symbolId = RuinsTemplatePages.symbolId(templateName);
+        ItemStack page = create(PageContent.symbol(new SymbolReference(symbolId)));
+        page.set(ModDataComponents.PAGE_SYMBOL_DISPLAY.get(),
+                RuinsTemplatePages.definition(templateName).display(symbolId));
+        return page;
+    }
+
     private static Map<String, CreativeSymbol> loadCreativeSymbols() {
         String resource = "/assets/rivencraft/creative_symbol_pages.json";
         try (var stream = PageItem.class.getResourceAsStream(resource)) {
@@ -321,6 +340,10 @@ public final class PageItem extends Item {
             return Component.translatable(metadata.nameTranslationKey()).withStyle(ChatFormatting.OBFUSCATED);
         }
         return reference.id().getNamespace().equals(Rivencraft.MOD_ID)
+                && RuinsTemplatePages.isSymbol(reference.id())
+                ? Component.translatableWithFallback(metadata.nameTranslationKey(),
+                        RuinsTemplatePages.fallbackName(reference.id()))
+                : reference.id().getNamespace().equals(Rivencraft.MOD_ID)
                 && reference.id().getPath().startsWith("biome/")
                 ? Component.translatableWithFallback(metadata.nameTranslationKey(),
                         BiomeSymbolPages.fallbackName(reference.id()))

src/main/java/net/dnorberg/rivencraft/mixin/LevelSkyBrightnessMixin.java

@@ -0,0 +1,40 @@
+package net.dnorberg.rivencraft.mixin;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.book.AgeDimensionService;
+import net.dnorberg.rivencraft.book.AgeRegistrySavedData;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.world.level.Level;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+/** Combines multiple celestial light sources into Minecraft's one skylight channel. */
+@Mixin(Level.class)
+public abstract class LevelSkyBrightnessMixin {
+    @Shadow private int skyDarken;
+
+    @Inject(method = "updateSkyBrightness", at = @At("TAIL"))
+    private void rivencraft$stackCelestialLight(CallbackInfo callback) {
+        if (!((Object) this instanceof ServerLevel level) || !level.dimensionType().hasSkyLight()) return;
+        // ServerLevel updates sky brightness in its constructor, before the
+        // MinecraftServer has registered even the Overworld level. Only an
+        // established Rivencraft Age can have a saved celestial profile.
+        if (!level.dimension().location().getNamespace().equals(Rivencraft.MOD_ID)
+                || !level.dimension().location().getPath().startsWith("age/")
+                || level.getServer().overworld() == null) return;
+        AgeRegistrySavedData.get(level).definitions().stream()
+                .filter(age -> AgeDimensionService.dimensionKey(age).equals(level.dimension()))
+                .findFirst().ifPresent(age -> {
+                    AgeSkyProfile sky = AgeSkyProfile.forAge(age);
+                    if (sky.bodies().isEmpty()) return;
+                    float light = sky.lightAt(level.getDayTime());
+                    float weather = (1.0F - level.getRainLevel(1.0F) * 5.0F / 16.0F)
+                            * (1.0F - level.getThunderLevel(1.0F) * 5.0F / 16.0F);
+                    skyDarken = (int) ((1.0F - light * weather) * 11.0F);
+                });
+    }
+}

src/main/java/net/dnorberg/rivencraft/mixin/RuinsAttemptMixin.java

@@ -0,0 +1,25 @@
+package net.dnorberg.rivencraft.mixin;
+
+import com.llamalad7.mixinextras.injector.ModifyExpressionValue;
+import net.dnorberg.rivencraft.compat.RuinsCompatibility;
+import net.minecraft.world.level.Level;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Pseudo;
+import org.spongepowered.asm.mixin.injection.At;
+
+/** Increase Ruins' per-chunk attempt loop only for Ages with duplicated Ruins pages. */
+@Pseudo
+@Mixin(targets = "atomicstryker.ruins.common.RuinGenerator", remap = false)
+public abstract class RuinsAttemptMixin {
+    @ModifyExpressionValue(method = "generateNormal", at = @At(value = "FIELD",
+            target = "Latomicstryker/ruins/common/FileHandler;triesPerChunkNormal:I"), remap = false)
+    private int rivencraft$normalAttempts(int configured, Level level) {
+        return RuinsCompatibility.attemptsPerChunk(level.dimension().location(), configured);
+    }
+
+    @ModifyExpressionValue(method = "generateNether", at = @At(value = "FIELD",
+            target = "Latomicstryker/ruins/common/FileHandler;triesPerChunkNether:I"), remap = false)
+    private int rivencraft$netherAttempts(int configured, Level level) {
+        return RuinsCompatibility.attemptsPerChunk(level.dimension().location(), configured);
+    }
+}

src/main/java/net/dnorberg/rivencraft/mixin/RuinsDimensionMixin.java

@@ -0,0 +1,38 @@
+package net.dnorberg.rivencraft.mixin;
+
+import net.dnorberg.rivencraft.compat.RuinsCompatibility;
+import net.dnorberg.rivencraft.compat.RuinsEventAdapter;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.util.RandomSource;
+import java.util.HashMap;
+import java.util.HashSet;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Pseudo;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+/** Ruins defaults to a fixed vanilla whitelist, so authored Ages need a narrow override. */
+@Pseudo
+@Mixin(targets = "atomicstryker.ruins.common.FileHandler", remap = false)
+public abstract class RuinsDimensionMixin {
+    @Shadow @Final private ResourceLocation dimension;
+    @Shadow @Final private HashMap<String, HashSet<?>> templates;
+
+    @Inject(method = "allowsDimension", at = @At("HEAD"), cancellable = true, remap = false)
+    private void rivencraft$allowAuthoredAge(String path, CallbackInfoReturnable<Boolean> result) {
+        if (RuinsCompatibility.isKnownAge(dimension)) {
+            result.setReturnValue(RuinsCompatibility.allowsAge(dimension));
+        }
+    }
+
+    @Inject(method = "getTemplate", at = @At("HEAD"), cancellable = true, remap = false)
+    private void rivencraft$selectAuthoredTemplate(RandomSource random, String biome,
+                                                    CallbackInfoReturnable<Object> result) {
+        if (RuinsCompatibility.isKnownAge(dimension)) {
+            result.setReturnValue(RuinsEventAdapter.chooseTemplate(dimension, templates.get(biome), random));
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/mixin/RuinsTemplateDimensionMixin.java

@@ -0,0 +1,27 @@
+package net.dnorberg.rivencraft.mixin;
+
+import net.dnorberg.rivencraft.compat.RuinsCompatibility;
+import net.dnorberg.rivencraft.compat.RuinsTemplatePages;
+import net.minecraft.resources.ResourceLocation;
+import org.spongepowered.asm.mixin.Final;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Pseudo;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+/** An authored Ruins page overrides a template's vanilla-only dimension list for that Age. */
+@Pseudo
+@Mixin(targets = "atomicstryker.ruins.common.RuinTemplate", remap = false)
+public abstract class RuinsTemplateDimensionMixin {
+    @Shadow @Final private String name;
+
+    @Inject(method = "acceptsDimension", at = @At("HEAD"), cancellable = true, remap = false)
+    private void rivencraft$allowAuthoredAge(String dimensionPath, CallbackInfoReturnable<Boolean> result) {
+        ResourceLocation dimension = ResourceLocation.fromNamespaceAndPath("rivencraft", dimensionPath);
+        if (RuinsCompatibility.isKnownAge(dimension)) {
+            result.setReturnValue(RuinsCompatibility.permits(dimension, RuinsTemplatePages.featureId(name)));
+        }
+    }
+}

src/main/java/net/dnorberg/rivencraft/mixin/client/ClientLevelSkyColorMixin.java

@@ -0,0 +1,40 @@
+package net.dnorberg.rivencraft.mixin.client;
+
+import net.dnorberg.rivencraft.client.ClientAgeCelestialAngles;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
+import net.minecraft.client.multiplayer.ClientLevel;
+import net.minecraft.world.phys.Vec3;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
+
+/** Keeps authored color pages visible in the sky without replacing vanilla sun and stars. */
+@Mixin(ClientLevel.class)
+public abstract class ClientLevelSkyColorMixin {
+    @Inject(method = "getSkyColor", at = @At("RETURN"), cancellable = true)
+    private void rivencraft$colorAuthoredSky(Vec3 position, float partialTick,
+                                             CallbackInfoReturnable<Vec3> result) {
+        ClientLevel level = (ClientLevel) (Object) this;
+        int color = ClientAgeCelestialAngles.skyColor(level.dimension());
+        if (color == -1 || ClientAgeCelestialAngles.staticSky(level.dimension())) return;
+        Vec3 natural = result.getReturnValue();
+        // Retain the vanilla day/night and precipitation darkening while replacing its hue.
+        AgeSkyProfile sky = ClientAgeCelestialAngles.sky(level.dimension());
+        double brightness = sky.bodies().isEmpty()
+                ? Math.max(natural.x, Math.max(natural.y, natural.z))
+                : Math.max(0.08D, sky.lightAt(level.getDayTime() + partialTick));
+        result.setReturnValue(Vec3.fromRGB24(color).scale(brightness));
+    }
+
+    @Inject(method = "getSkyDarken", at = @At("RETURN"), cancellable = true)
+    private void rivencraft$stackClientCelestialLight(float partialTick,
+                                                       CallbackInfoReturnable<Float> result) {
+        ClientLevel level = (ClientLevel) (Object) this;
+        AgeSkyProfile sky = ClientAgeCelestialAngles.sky(level.dimension());
+        if (sky.bodies().isEmpty() || !level.dimensionType().hasSkyLight()) return;
+        float weather = (1.0F - level.getRainLevel(partialTick) * 5.0F / 16.0F)
+                * (1.0F - level.getThunderLevel(partialTick) * 5.0F / 16.0F);
+        result.setReturnValue(0.2F + 0.8F * sky.lightAt(level.getDayTime() + partialTick) * weather);
+    }
+}

src/main/java/net/dnorberg/rivencraft/mixin/client/LevelRendererMixin.java

@@ -2,20 +2,37 @@ package net.dnorberg.rivencraft.mixin.client;
 
 import com.mojang.math.Axis;
 import net.dnorberg.rivencraft.client.ClientAgeCelestialAngles;
+import net.dnorberg.rivencraft.client.RivencraftSkyEffects;
+import net.minecraft.client.Camera;
 import net.minecraft.client.multiplayer.ClientLevel;
 import net.minecraft.client.renderer.LevelRenderer;
+import org.joml.Matrix4f;
 import org.joml.Quaternionf;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.Shadow;
 import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.Redirect;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 
 /** Rotates the vanilla sun, moon, and star path by each Age's saved angle. */
 @Mixin(LevelRenderer.class)
 public abstract class LevelRendererMixin {
+    private static final RivencraftSkyEffects RIVENCRAFT_SKY = new RivencraftSkyEffects();
+
     @Shadow
     private ClientLevel level;
 
+    @Inject(method = "renderSky", at = @At("HEAD"), cancellable = true)
+    private void rivencraft$renderAgeSky(Matrix4f frustumMatrix, Matrix4f projectionMatrix,
+                                        float partialTick, Camera camera, boolean isFoggy,
+                                        Runnable skyFogSetup, CallbackInfo callback) {
+        if (!level.dimension().location().getNamespace().equals("rivencraft")) return;
+        ClientAgeCelestialAngles.requestIfMissing(level.dimension());
+        if (RIVENCRAFT_SKY.renderSky(level, (int) level.getGameTime(), partialTick,
+                frustumMatrix, camera, projectionMatrix, isFoggy, skyFogSetup)) callback.cancel();
+    }
+
     @Redirect(
             method = "renderSky",
             at = @At(

src/main/java/net/dnorberg/rivencraft/network/AgeCelestialAnglePayload.java

@@ -1,6 +1,7 @@
 package net.dnorberg.rivencraft.network;
 
 import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.book.AgeSkyProfile;
 import net.minecraft.core.registries.Registries;
 import net.minecraft.network.RegistryFriendlyByteBuf;
 import net.minecraft.network.codec.StreamCodec;
@@ -9,8 +10,8 @@ import net.minecraft.resources.ResourceKey;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.level.Level;
 
-/** Synchronizes an Age's saved celestial-plane rotation to clients. */
-public record AgeCelestialAnglePayload(ResourceKey<Level> dimension, float angle)
+/** Synchronizes an Age's saved celestial-plane rotation and authored sky to clients. */
+public record AgeCelestialAnglePayload(ResourceKey<Level> dimension, float angle, AgeSkyProfile sky)
         implements CustomPacketPayload {
     public static final Type<AgeCelestialAnglePayload> TYPE = new Type<>(
             ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "age_celestial_angle")
@@ -20,9 +21,34 @@ public record AgeCelestialAnglePayload(ResourceKey<Level> dimension, float angle
                     (buffer, payload) -> {
                         buffer.writeResourceKey(payload.dimension());
                         buffer.writeFloat(payload.angle());
+                        buffer.writeEnum(payload.sky().style());
+                        buffer.writeInt(payload.sky().color());
+                        buffer.writeVarInt(payload.sky().bodies().size());
+                        for (AgeSkyProfile.Body body : payload.sky().bodies()) {
+                            buffer.writeEnum(body.kind());
+                            buffer.writeInt(body.color());
+                            buffer.writeFloat(body.size());
+                            buffer.writeFloat(body.angle());
+                            buffer.writeDouble(body.period());
+                            buffer.writeFloat(body.phase());
+                            buffer.writeBoolean(body.clockwise());
+                        }
                     },
-                    buffer -> new AgeCelestialAnglePayload(
-                            buffer.readResourceKey(Registries.DIMENSION), buffer.readFloat())
+                    buffer -> {
+                        ResourceKey<Level> dimension = buffer.readResourceKey(Registries.DIMENSION);
+                        float angle = buffer.readFloat();
+                        AgeSkyProfile.Style style = buffer.readEnum(AgeSkyProfile.Style.class);
+                        int color = buffer.readInt();
+                        int count = buffer.readVarInt();
+                        if (count < 0 || count > 20) throw new IllegalArgumentException("Invalid celestial body count");
+                        java.util.List<AgeSkyProfile.Body> bodies = new java.util.ArrayList<>(count);
+                        for (int i = 0; i < count; i++) bodies.add(new AgeSkyProfile.Body(
+                                buffer.readEnum(AgeSkyProfile.Kind.class), buffer.readInt(),
+                                buffer.readFloat(), buffer.readFloat(), buffer.readDouble(), buffer.readFloat(),
+                                buffer.readBoolean()));
+                        return new AgeCelestialAnglePayload(dimension, angle,
+                                new AgeSkyProfile(style, color, bodies));
+                    }
             );
 
     @Override

src/main/java/net/dnorberg/rivencraft/network/ModNetworking.java

@@ -61,7 +61,7 @@ public final class ModNetworking {
     }
 
     public static void register(RegisterPayloadHandlersEvent event) {
-        PayloadRegistrar registrar = event.registrar("17");
+        PayloadRegistrar registrar = event.registrar("18");
         registrar.playToServer(RequestDescriptiveBookScreenPayload.TYPE, RequestDescriptiveBookScreenPayload.STREAM_CODEC,
                 ModNetworking::requestDescriptiveBookScreen);
         registrar.playToClient(OpenDescriptiveBookScreenPayload.TYPE, OpenDescriptiveBookScreenPayload.STREAM_CODEC,
@@ -81,6 +81,8 @@ public final class ModNetworking {
                 ClientLinkPreviewHandler::handle);
         registrar.playToClient(AgeCelestialAnglePayload.TYPE, AgeCelestialAnglePayload.STREAM_CODEC,
                 ClientAgeCelestialAngles::handle);
+        registrar.playToServer(RequestAgeSkyPayload.TYPE, RequestAgeSkyPayload.STREAM_CODEC,
+                ModNetworking::requestAgeSky);
         registrar.playToClient(SereneAgeWhitelistPayload.TYPE, SereneAgeWhitelistPayload.STREAM_CODEC,
                 ClientSereneAgeWhitelist::handle);
         registrar.playToClient(WritingDeskCatalogPayload.TYPE, WritingDeskCatalogPayload.STREAM_CODEC,
@@ -93,6 +95,16 @@ public final class ModNetworking {
                 ModNetworking::setLinkModifierSeed);
     }
 
+    private static void requestAgeSky(RequestAgeSkyPayload payload, IPayloadContext context) {
+        if (!(context.player() instanceof ServerPlayer player)) return;
+        // Portal renderers may request another Age. Only return registered Age data,
+        // never an arbitrary client-supplied dimension or generated terrain.
+        AgeRegistrySavedData.get(player.serverLevel()).definitions().stream()
+                .filter(age -> AgeDimensionService.dimensionKey(age).equals(payload.dimension()))
+                .findFirst()
+                .ifPresent(age -> AgeCelestialAngleSync.send(player, age));
+    }
+
     private static void setBookBinderTitle(SetBookBinderTitlePayload payload, IPayloadContext context) {
         if (context.player() instanceof ServerPlayer player
                 && player.containerMenu instanceof BookBinderMenu menu
@@ -348,8 +360,7 @@ public final class ModNetworking {
 
     /** Sky effects, not dimension IDs, decide the backdrop for custom Ages. */
     private static int previewSkyColor(ServerLevel level, BlockPos origin) {
-        return AgeEnvironmentCompiler.previewSkyColor(level.dimensionType().effectsLocation(),
-                level.getBiome(origin).value().getSkyColor());
+        return AgeEnvironmentCompiler.previewSkyColor(level, origin);
     }
 
     private static InteractionHand hand(boolean offhand) {

src/main/java/net/dnorberg/rivencraft/network/RequestAgeSkyPayload.java

@@ -0,0 +1,24 @@
+package net.dnorberg.rivencraft.network;
+
+import net.dnorberg.rivencraft.Rivencraft;
+import net.minecraft.core.registries.Registries;
+import net.minecraft.network.RegistryFriendlyByteBuf;
+import net.minecraft.network.codec.StreamCodec;
+import net.minecraft.network.protocol.common.custom.CustomPacketPayload;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.level.Level;
+
+/** Requests the saved sky profile when a renderer reaches an Age before dimension-change sync. */
+public record RequestAgeSkyPayload(ResourceKey<Level> dimension) implements CustomPacketPayload {
+    public static final Type<RequestAgeSkyPayload> TYPE = new Type<>(
+            ResourceLocation.fromNamespaceAndPath(Rivencraft.MOD_ID, "request_age_sky"));
+    public static final StreamCodec<RegistryFriendlyByteBuf, RequestAgeSkyPayload> STREAM_CODEC = StreamCodec.of(
+            (buffer, payload) -> buffer.writeResourceKey(payload.dimension()),
+            buffer -> new RequestAgeSkyPayload(buffer.readResourceKey(Registries.DIMENSION)));
+
+    @Override
+    public Type<? extends CustomPacketPayload> type() {
+        return TYPE;
+    }
+}

src/main/java/net/dnorberg/rivencraft/registry/ModCreativeTabs.java

@@ -58,7 +58,7 @@ public final class ModCreativeTabs {
                     .build());
 
     private static final List<String> CATEGORY_ORDER = List.of(
-            "terrain", "biome", "cave_biome", "biome_generation", "weather", "season", "lighting", "sky", "celestial", "block", "fluid", "feature", "environment", "corrupted");
+            "terrain", "biome", "cave_biome", "biome_generation", "weather", "season", "lighting", "sky", "color", "number", "celestial", "block", "fluid", "feature", "ruins", "environment", "corrupted");
 
     public static final Map<ResourceLocation, DeferredHolder<CreativeModeTab, CreativeModeTab>> SYMBOL_PAGES =
             registerSymbolPageTabs();

src/main/java/net/dnorberg/rivencraft/writing/SymbolCatalog.java

@@ -7,6 +7,7 @@ import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
 import net.dnorberg.rivencraft.Rivencraft;
+import net.dnorberg.rivencraft.compat.RuinsTemplatePages;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.core.RegistryAccess;
 import net.minecraft.core.registries.Registries;
@@ -73,6 +74,9 @@ public final class SymbolCatalog {
                             BiomeSymbolPages.definition(id)));
             BlockSymbolPages.availableBlocks().forEach(id -> loaded.putIfAbsent(
                     BlockSymbolPages.symbolId(id), BlockSymbolPages.definition(id)));
+            RuinsTemplatePages.refresh();
+            RuinsTemplatePages.templates().forEach(name -> loaded.putIfAbsent(
+                    RuinsTemplatePages.symbolId(name), RuinsTemplatePages.definition(name)));
             symbols = Map.copyOf(loaded);
             Rivencraft.LOGGER.info("Loaded {} writing symbols", loaded.size());
         }

src/main/java/net/dnorberg/rivencraft/writing/SymbolSemantics.java

@@ -77,12 +77,20 @@ public record SymbolSemantics(Role role, Value value) {
                 "native", "single", "tiled", "grid", "tiny", "small", "medium", "large", "huge"),
         BIOME("biome", Kind.RESOURCE),
         LIGHTING("lighting", Kind.CHOICE, "normal", "dark", "bright"),
-        SKY("sky", Kind.CHOICE, "overworld", "nether", "end"),
+        SKY("sky", Kind.CHOICE, "overworld", "nether", "end", "static"),
+        SKY_COLOR("sky_color", Kind.CHOICE,
+                "red", "orange", "yellow", "green", "blue", "purple", "white", "black"),
+        COLOR("color", Kind.CHOICE, "red", "green", "blue", "black", "white"),
+        COLOR_NUMBER("color_number", Kind.NUMBER),
         WEATHER("weather", Kind.CHOICE,
                 "normal", "fast", "slow", "off", "always", "cloudy", "rain", "snow", "storm"),
         SEASON("season", Kind.CHOICE,
                 "no_seasons", "seasons", "eternal_winter", "eternal_summer", "eternal_fall", "eternal_spring"),
-        CELESTIAL("celestial", Kind.CHOICE, "normal_time"),
+        CELESTIAL("celestial", Kind.CHOICE, "normal_time", "sun", "moon"),
+        CELESTIAL_COLOR("celestial_color", Kind.CHOICE,
+                "red", "orange", "yellow", "green", "blue", "purple", "white", "black"),
+        DIRECTION_MODIFIER("direction_modifier", Kind.CHOICE, "clockwise", "counterclockwise"),
+        SIZE_MODIFIER("size_modifier", Kind.NUMBER),
         PERIOD_MODIFIER("period_modifier", Kind.NUMBER),
         ANGLE_MODIFIER("angle_modifier", Kind.NUMBER),
         PHASE_MODIFIER("phase_modifier", Kind.NUMBER),
@@ -109,6 +117,9 @@ public record SymbolSemantics(Role role, Value value) {
             if (!(value instanceof NumberValue number)) return false;
             return switch (this) {
                 case PERIOD_MODIFIER -> number.amount() >= 0.0 && number.amount() <= 2.0;
+                case SIZE_MODIFIER -> number.amount() >= 0.25 && number.amount() <= 3.0;
+                case COLOR_NUMBER -> number.amount() >= 0.0 && number.amount() <= 24.0
+                        && number.amount() == Math.floor(number.amount());
                 case ANGLE_MODIFIER, PHASE_MODIFIER -> number.amount() >= 0.0 && number.amount() < 360.0;
                 default -> false;
             };
@@ -119,6 +130,8 @@ public record SymbolSemantics(Role role, Value value) {
                 case RESOURCE -> "a canonical namespaced ID";
                 case CHOICE -> "one of " + choices.stream().sorted().toList();
                 case NUMBER -> this == PERIOD_MODIFIER ? "a finite number in [0, 2]"
+                        : this == SIZE_MODIFIER ? "a finite number in [0.25, 3]"
+                        : this == COLOR_NUMBER ? "an integer D'ni digit in [0, 24]"
                         : "a finite number in [0, 360) degrees";
             };
         }

src/main/java/net/dnorberg/rivencraft/writing/WritingGrammar.java

@@ -45,6 +45,7 @@ public final class WritingGrammar {
         int lastStage = -1;
         int biomeCount = 0;
         ParsedSymbol pendingBlock = null;
+        ParsedSymbol pendingColorNumber = null;
         for (int index = 0; index < writing.entries().size(); index++) {
             WritingEntry entry = writing.entries().get(index);
             if (entry.kind() == WritingEntry.Kind.LINK_PANEL) {
@@ -73,6 +74,18 @@ public final class WritingGrammar {
             Role role = semantics.orElseThrow().role();
             ParsedSymbol parsed = new ParsedSymbol(index, reference, semantics.orElseThrow());
             symbols.add(parsed);
+            if (pendingColorNumber != null && role != Role.COLOR && role != Role.COLOR_NUMBER) {
+                diagnostics.add(new Diagnostic(Code.MISPLACED_MODIFIER, pendingColorNumber.index(),
+                        "A number page must be immediately followed by a color page"));
+                pendingColorNumber = null;
+            }
+            if (role == Role.COLOR_NUMBER) {
+                if (pendingColorNumber != null) diagnostics.add(new Diagnostic(Code.MISPLACED_MODIFIER,
+                        pendingColorNumber.index(), "A number page must be immediately followed by a color page"));
+                pendingColorNumber = parsed;
+            } else if (role == Role.COLOR) {
+                pendingColorNumber = null;
+            }
             if (modifier(role)) {
                 // Legacy modifier pages pop and combine an earlier modifier of the same
                 // kind. Only the final pending value can be left dangling.
@@ -96,7 +109,7 @@ public final class WritingGrammar {
                 }
                 pendingBlock = null;
             }
-            if (role == Role.ANGLE_MODIFIER || role == Role.WEATHER
+            if (role == Role.WEATHER
                     && parsed.semantics().value() instanceof ChoiceValue choice
                     && UNSUPPORTED_WEATHER.contains(choice.id())) {
                 diagnostics.add(new Diagnostic(Code.UNSUPPORTED_ENVIRONMENT, index,
@@ -115,13 +128,15 @@ public final class WritingGrammar {
             }
             if (role == Role.BIOME) biomeCount++;
             int stage = stage(role);
-            if (stage < lastStage && !modifier(role)) {
+            if (stage < lastStage && !modifier(role) && role != Role.COLOR && role != Role.COLOR_NUMBER) {
                 diagnostics.add(new Diagnostic(Code.OUT_OF_ORDER,
                         index, "Move this " + role.id() + " page before later grammar categories"));
-            } else {
+            } else if (role != Role.COLOR && role != Role.COLOR_NUMBER) {
                 lastStage = stage;
             }
         }
+        if (pendingColorNumber != null) diagnostics.add(new Diagnostic(Code.DANGLING_MODIFIER,
+                pendingColorNumber.index(), "A number page must be followed by a color page"));
         if (panels == 0) diagnostics.add(new Diagnostic(Code.MISSING_PANEL, -1,
                 "Add a Link Panel as the first page"));
         for (ParsedSymbol dangling : pendingModifiers.values()) {
@@ -142,7 +157,10 @@ public final class WritingGrammar {
         }
         for (Role required : List.of(Role.TERRAIN, Role.BIOME_CONTROLLER, Role.WEATHER,
                 Role.LIGHTING, Role.CELESTIAL)) {
-            if (!singular.containsKey(required)) diagnostics.add(new Diagnostic(Code.INCOMPLETE, -1,
+            boolean present = required == Role.CELESTIAL
+                    ? symbols.stream().anyMatch(symbol -> symbol.semantics().role() == Role.CELESTIAL)
+                    : singular.containsKey(required);
+            if (!present) diagnostics.add(new Diagnostic(Code.INCOMPLETE, -1,
                     "The Age compiler will fill the missing " + required.id() + " branch from the Age seed"));
         }
         if (controller != null && controller.semantics().value() instanceof ChoiceValue choice) {
@@ -160,13 +178,15 @@ public final class WritingGrammar {
 
     private static boolean singular(Role role) {
         return switch (role) {
-            case TERRAIN, BIOME_CONTROLLER, WEATHER, SEASON, LIGHTING, SKY, CELESTIAL -> true;
+            case TERRAIN, BIOME_CONTROLLER, WEATHER, SEASON, LIGHTING, SKY -> true;
             default -> false;
         };
     }
 
     private static boolean modifier(Role role) {
-        return role == Role.PERIOD_MODIFIER || role == Role.ANGLE_MODIFIER || role == Role.PHASE_MODIFIER;
+        return role == Role.PERIOD_MODIFIER || role == Role.ANGLE_MODIFIER
+                || role == Role.PHASE_MODIFIER || role == Role.SIZE_MODIFIER
+                || role == Role.CELESTIAL_COLOR || role == Role.DIRECTION_MODIFIER;
     }
 
     private static int stage(Role role) {
@@ -177,8 +197,10 @@ public final class WritingGrammar {
             case WEATHER -> 3;
             case SEASON -> 4;
             case LIGHTING -> 5;
-            case SKY -> 6;
-            case PERIOD_MODIFIER, ANGLE_MODIFIER, PHASE_MODIFIER -> 7;
+            case SKY, SKY_COLOR -> 6;
+            case COLOR, COLOR_NUMBER -> 6;
+            case PERIOD_MODIFIER, ANGLE_MODIFIER, PHASE_MODIFIER, SIZE_MODIFIER,
+                    CELESTIAL_COLOR, DIRECTION_MODIFIER -> 7;
             case CELESTIAL -> 8;
             case BLOCK, FEATURE, ENVIRONMENT, CORRUPTED -> 9;
         };

src/main/resources/assets/rivencraft/blockstates/book_receptacle.json

@@ -1 +1,10 @@
-{"variants":{"facing=north":{"model":"rivencraft:block/book_receptacle","y":180},"facing=east":{"model":"rivencraft:block/book_receptacle","y":270},"facing=south":{"model":"rivencraft:block/book_receptacle"},"facing=west":{"model":"rivencraft:block/book_receptacle","y":90},"facing=up":{"model":"rivencraft:block/book_receptacle","x":270},"facing=down":{"model":"rivencraft:block/book_receptacle","x":90}}}
+{
+  "multipart": [
+    {"when": {"facing": "north"}, "apply": {"model": "rivencraft:block/book_receptacle", "y": 180}},
+    {"when": {"facing": "east"}, "apply": {"model": "rivencraft:block/book_receptacle", "y": 270}},
+    {"when": {"facing": "south"}, "apply": {"model": "rivencraft:block/book_receptacle"}},
+    {"when": {"facing": "west"}, "apply": {"model": "rivencraft:block/book_receptacle", "y": 90}},
+    {"when": {"facing": "up"}, "apply": {"model": "rivencraft:block/book_receptacle", "x": 90}},
+    {"when": {"facing": "down"}, "apply": {"model": "rivencraft:block/book_receptacle", "x": 270, "y": 180}}
+  ]
+}

src/main/resources/assets/rivencraft/lang/en_us.json

@@ -223,6 +223,44 @@
   "symbol.rivencraft.sky.nether.description": "Use the Nether sky and red preview background.",
   "symbol.rivencraft.sky.end": "End Sky",
   "symbol.rivencraft.sky.end.description": "Use the End sky and dark preview background.",
+  "symbol.rivencraft.sky.static": "Static Sky",
+  "symbol.rivencraft.sky.static.description": "Fill the sky with shifting television static.",
+  "symbol.rivencraft.color.red": "Red Color",
+  "symbol.rivencraft.color.red.description": "Add red to the next Sky, Sun, or Moon. A number page directly before this page sets its strength.",
+  "symbol.rivencraft.color.green": "Green Color",
+  "symbol.rivencraft.color.green.description": "Add green to the next Sky, Sun, or Moon. A number page directly before this page sets its strength.",
+  "symbol.rivencraft.color.blue": "Blue Color",
+  "symbol.rivencraft.color.blue.description": "Add blue to the next Sky, Sun, or Moon. A number page directly before this page sets its strength.",
+  "symbol.rivencraft.color.white": "White Color",
+  "symbol.rivencraft.color.white.description": "Add equal brightness to red, green, and blue in the next Sky, Sun, or Moon.",
+  "symbol.rivencraft.color.black": "Black Color",
+  "symbol.rivencraft.color.black.description": "Subtract equal brightness from red, green, and blue in the next Sky, Sun, or Moon.",
+  "symbol.rivencraft.number.0": "D'ni 0",
+  "symbol.rivencraft.number.1": "D'ni 1",
+  "symbol.rivencraft.number.2": "D'ni 2",
+  "symbol.rivencraft.number.3": "D'ni 3",
+  "symbol.rivencraft.number.4": "D'ni 4",
+  "symbol.rivencraft.number.5": "D'ni 5",
+  "symbol.rivencraft.number.6": "D'ni 6",
+  "symbol.rivencraft.number.7": "D'ni 7",
+  "symbol.rivencraft.number.8": "D'ni 8",
+  "symbol.rivencraft.number.9": "D'ni 9",
+  "symbol.rivencraft.number.10": "D'ni 10",
+  "symbol.rivencraft.number.11": "D'ni 11",
+  "symbol.rivencraft.number.12": "D'ni 12",
+  "symbol.rivencraft.number.13": "D'ni 13",
+  "symbol.rivencraft.number.14": "D'ni 14",
+  "symbol.rivencraft.number.15": "D'ni 15",
+  "symbol.rivencraft.number.16": "D'ni 16",
+  "symbol.rivencraft.number.17": "D'ni 17",
+  "symbol.rivencraft.number.18": "D'ni 18",
+  "symbol.rivencraft.number.19": "D'ni 19",
+  "symbol.rivencraft.number.20": "D'ni 20",
+  "symbol.rivencraft.number.21": "D'ni 21",
+  "symbol.rivencraft.number.22": "D'ni 22",
+  "symbol.rivencraft.number.23": "D'ni 23",
+  "symbol.rivencraft.number.24": "D'ni 24",
+  "symbol.rivencraft.number.description": "Set the next color page to this D'ni number times 10. Without a number page, the Age chooses a random number from 0 to 24.",
   "symbol.rivencraft.weather.normal": "Normal Weather",
   "symbol.rivencraft.weather.normal.description": "Use the normal weather cycle.",
   "symbol.rivencraft.weather.fast": "Fast Weather",
@@ -249,6 +287,28 @@
   "symbol.rivencraft.season.eternal_spring.description": "Hold this Age in midspring.",
   "symbol.rivencraft.celestial.normal_time": "Normal Time",
   "symbol.rivencraft.celestial.normal_time.description": "Use a normal-length celestial cycle.",
+  "symbol.rivencraft.celestial.sun": "Sun",
+  "symbol.rivencraft.celestial.sun.description": "Add one independently moving sun to the sky.",
+  "symbol.rivencraft.celestial.moon": "Moon",
+  "symbol.rivencraft.celestial.moon.description": "Add one independently moving moon to the sky.",
+  "symbol.rivencraft.size.small": "Small Celestial",
+  "symbol.rivencraft.size.small.description": "Halve the apparent size of the next sun or moon.",
+  "symbol.rivencraft.size.normal": "Normal Celestial Size",
+  "symbol.rivencraft.size.normal.description": "Set the next sun or moon to normal apparent size.",
+  "symbol.rivencraft.size.large": "Large Celestial",
+  "symbol.rivencraft.size.large.description": "Double the apparent size of the next sun or moon.",
+  "symbol.rivencraft.angle.north": "North Celestial Angle",
+  "symbol.rivencraft.angle.north.description": "Orient the next sun or moon toward the north.",
+  "symbol.rivencraft.angle.east": "East Celestial Angle",
+  "symbol.rivencraft.angle.east.description": "Orient the next sun or moon toward the east.",
+  "symbol.rivencraft.angle.south": "South Celestial Angle",
+  "symbol.rivencraft.angle.south.description": "Orient the next sun or moon toward the south.",
+  "symbol.rivencraft.angle.west": "West Celestial Angle",
+  "symbol.rivencraft.angle.west.description": "Orient the next sun or moon toward the west.",
+  "symbol.rivencraft.direction.clockwise": "Clockwise Motion",
+  "symbol.rivencraft.direction.clockwise.description": "Move the next sun or moon clockwise in its orbital plane.",
+  "symbol.rivencraft.direction.counterclockwise": "Counterclockwise Motion",
+  "symbol.rivencraft.direction.counterclockwise.description": "Move the next sun or moon counterclockwise in its orbital plane.",
   "symbol.rivencraft.period.zero": "Zero Length",
   "symbol.rivencraft.period.zero.description": "Stop the celestial cycle at its written phase.",
   "symbol.rivencraft.period.half": "Half Length",
@@ -371,6 +431,8 @@
   "rivencraft.ponder.crystal_portal.text_3": "Insert a bound Linking or Descriptive Book to activate the portal.",
   "rivencraft.ponder.crystal_portal.text_4": "Step through the portal. Remove the book to close it.",
   "itemGroup.rivencraft": "Rivencraft",
+  "itemGroup.rivencraft.pages.ruins": "Rivencraft Ruins Pages",
+  "symbol.rivencraft.ruins.description": "Allows this Ruins template to appear in the Age.",
   "itemGroup.rivencraft.pages.link": "Rivencraft Link Pages",
   "itemGroup.rivencraft.pages.terrain": "Rivencraft Terrain Pages",
   "itemGroup.rivencraft.pages.biome": "Rivencraft Biome Pages",
@@ -380,6 +442,8 @@
   "itemGroup.rivencraft.pages.season": "Rivencraft Season Pages",
   "itemGroup.rivencraft.pages.lighting": "Rivencraft Lighting Pages",
   "itemGroup.rivencraft.pages.sky": "Rivencraft Sky Pages",
+  "itemGroup.rivencraft.pages.color": "Rivencraft Color Pages",
+  "itemGroup.rivencraft.pages.number": "Rivencraft Number Pages",
   "itemGroup.rivencraft.pages.celestial": "Rivencraft Celestial Pages",
   "itemGroup.rivencraft.pages.block": "Rivencraft Block Pages",
   "itemGroup.rivencraft.pages.fluid": "Rivencraft Fluid Pages",

src/main/resources/assets/rivencraft/models/block/crystal_portal.json

@@ -1 +1 @@
-{"render_type":"minecraft:translucent","ambientocclusion":false,"textures":{"particle":"rivencraft:block/crystal_portal","portal":"rivencraft:block/crystal_portal"},"elements":[{"from":[0,0,6],"to":[16,16,10],"shade":false,"faces":{"north":{"texture":"#portal"},"south":{"texture":"#portal"}}}]}
+{"render_type":"minecraft:translucent","ambientocclusion":false,"textures":{"particle":"rivencraft:block/crystal_portal","portal":"rivencraft:block/crystal_portal"},"elements":[{"from":[0,0,6],"to":[16,16,10],"shade":false,"faces":{"north":{"texture":"#portal","tintindex":0},"south":{"texture":"#portal","tintindex":0}}}]}

src/main/resources/data/rivencraft/rivencraft/symbols/angle/east.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.angle.east","description":"symbol.rivencraft.angle.east.description","category":"rivencraft:celestial","semantics":{"role":"angle_modifier","value":90.0},"poem":"Transform East Illuminate Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/angle/north.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.angle.north","description":"symbol.rivencraft.angle.north.description","category":"rivencraft:celestial","semantics":{"role":"angle_modifier","value":0.0},"poem":"Transform North Illuminate Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/angle/south.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.angle.south","description":"symbol.rivencraft.angle.south.description","category":"rivencraft:celestial","semantics":{"role":"angle_modifier","value":180.0},"poem":"Transform South Illuminate Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/angle/west.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.angle.west","description":"symbol.rivencraft.angle.west.description","category":"rivencraft:celestial","semantics":{"role":"angle_modifier","value":270.0},"poem":"Transform West Illuminate Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/celestial/moon.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.celestial.moon","description":"symbol.rivencraft.celestial.moon.description","category":"rivencraft:celestial","semantics":{"role":"celestial","value":"moon"},"poem":"Transform Time Shadow Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/celestial/sun.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.celestial.sun","description":"symbol.rivencraft.celestial.sun.description","category":"rivencraft:celestial","semantics":{"role":"celestial","value":"sun"},"poem":"Transform Time Illuminate Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/color/black.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.color.black","description":"symbol.rivencraft.color.black.description","category":"rivencraft:color","semantics":{"role":"color","value":"black"},"poem":"Ethereal Black Transform Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/color/blue.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.color.blue","description":"symbol.rivencraft.color.blue.description","category":"rivencraft:color","semantics":{"role":"color","value":"blue"},"poem":"Ethereal Blue Transform Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/color/green.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.color.green","description":"symbol.rivencraft.color.green.description","category":"rivencraft:color","semantics":{"role":"color","value":"green"},"poem":"Ethereal Green Transform Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/color/red.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.color.red","description":"symbol.rivencraft.color.red.description","category":"rivencraft:color","semantics":{"role":"color","value":"red"},"poem":"Ethereal Red Transform Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/color/white.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.color.white","description":"symbol.rivencraft.color.white.description","category":"rivencraft:color","semantics":{"role":"color","value":"white"},"poem":"Ethereal White Transform Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/direction/clockwise.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.direction.clockwise","description":"symbol.rivencraft.direction.clockwise.description","category":"rivencraft:celestial","semantics":{"role":"direction_modifier","value":"clockwise"},"poem":"Transform Time Clockwise Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/direction/counterclockwise.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.direction.counterclockwise","description":"symbol.rivencraft.direction.counterclockwise.description","category":"rivencraft:celestial","semantics":{"role":"direction_modifier","value":"counterclockwise"},"poem":"Transform Time Reverse Motion"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/0.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.0","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":0},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/1.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.1","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":1},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/10.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.10","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":10},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/11.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.11","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":11},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/12.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.12","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":12},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/13.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.13","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":13},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/14.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.14","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":14},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/15.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.15","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":15},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/16.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.16","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":16},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/17.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.17","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":17},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/18.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.18","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":18},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/19.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.19","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":19},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/2.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.2","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":2},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/20.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.20","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":20},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/21.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.21","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":21},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/22.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.22","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":22},"poem":"Transform Time System Balance"}

src/main/resources/data/rivencraft/rivencraft/symbols/number/23.json

@@ -0,0 +1 @@
+{"schema_version":2,"name":"symbol.rivencraft.number.23","description":"symbol.rivencraft.number.description","category":"rivencraft:number","semantics":{"role":"color_number","value":23},"poem":"Transform Time System Balance"}