Difficulty Lock

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

Evidence

Ran on Kiln's test stand (2026-11-04): ModFabric did not start: java.lang.NoSuchMethodError: 'java.util.Optional net.fabricmc.loader.api.FabricLoader.getModContainer(java.lang.String)'; ModFabricClient did not start: java.lang.NoSuchMethodError: 'java.util.Optional net.fabricmc.loader.api.FabricLoader.getModContainer(java.lang.String)'.

What it needs from Kiln

Mixin
net.fabricmc.fabric.api.event.lifecycle.v1.ServerLevelEvents
net.fabricmc.fabric.api.event.lifecycle.v1.ServerLevelEvents.Load
net.minecraft.client.gui.components.CycleButton
net.minecraft.client.gui.screens.worldselection.CreateWorldScreen
net.minecraft.client.gui.screens.worldselection.WorldCreationUiState
net.minecraft.client.gui.screens.worldselection.WorldCreationUiState.SelectedGameMode
net.minecraft.server.MinecraftServer
net.minecraft.world.Difficulty
net.minecraft.world.level.storage.LevelData
net.minecraft.world.level.storage.WorldData
ServerLevel.getLevelData()
ServerLevel.getServer()

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

🔒 Sets a difficulty in any world, optionally locked, or force a hardcore mode requirement.

Scan

Scanned on 4 November 2026 against Kiln 0.2.0, file difficultylock-26.3.0-5.2.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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