Superflat Biome Extension

Calls something that is on Kiln's roadmap. Parts of it may already run.

Evidence

Ran on Kiln's test stand (2026-11-04): SuperflatBiomeExtension did not start: java.lang.NoClassDefFoundError: net/minecraft/world/level/levelgen/material/rule/MaterialRule.

What it needs from Kiln

an access widener
Mixin
net.fabricmc.fabric.api.event.registry.DynamicRegistries
net.fabricmc.fabric.api.event.registry.FabricRegistryBuilder
net.fabricmc.fabric.api.event.registry.RegistryAttribute
net.minecraft.SharedConstants
net.minecraft.TracingExecutor
net.minecraft.core.BlockPos.MutableBlockPos
net.minecraft.core.HolderGetter
net.minecraft.core.HolderGetter.Provider
net.minecraft.core.HolderLookup.RegistryLookup
net.minecraft.core.HolderSet
net.minecraft.core.RegistryAccess
net.minecraft.core.RegistryAccess.Frozen
net.minecraft.core.RegistrySetBuilder
net.minecraft.core.registries.codec.RegistryCodecs
net.minecraft.data.worldgen.BootstrapContext
net.minecraft.data.worldgen.NoiseData
net.minecraft.data.worldgen.TerrainProvider
net.minecraft.data.worldgen.material.EndMaterialRules
net.minecraft.data.worldgen.material.VanillaMaterialConditions
net.minecraft.resources.RegistryOps
net.minecraft.server.level.WorldGenRegion
net.minecraft.tags.TagKey
net.minecraft.util.CubicSpline
net.minecraft.util.CubicSpline.Multipoint
net.minecraft.util.Util
net.minecraft.util.profiling.Profiler
net.minecraft.util.profiling.ProfilerFiller
net.minecraft.util.profiling.Zone
net.minecraft.world.level.ChunkPos
net.minecraft.world.level.LevelHeightAccessor
net.minecraft.world.level.NaturalSpawner
net.minecraft.world.level.NoiseColumn
net.minecraft.world.level.StructureManager
net.minecraft.world.level.biome.Biome
net.minecraft.world.level.biome.BiomeGenerationSettings
net.minecraft.world.level.biome.BiomeGenerationSettings.PlainBuilder
net.minecraft.world.level.biome.BiomeManager
net.minecraft.world.level.biome.BiomeSource
net.minecraft.world.level.biome.Biomes
net.minecraft.world.level.biome.Climate
and 70 more

On the roadmap: Minecraft's libraries and client API (0.2), Code next to data (0.3), Mixin (0.5)

In the author's words

Adds a flat world type with regular biome distribution.

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file superflatbiomeextension-0.3-beta-26.3-fabric.jar. The scan reads the mod's classes; it does not run them.

Reports from players

No reports from players yet.

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