Overall, I have made these changes to my Main (and only) class.
package com.hastev.biomes;
import net.minecraft.util.RegistryKey;
...
@Mod("tutorial")
public class Main {
public static final RegistryKey<Biome> stony = RegistryKey.create(Registry.BIOME_REGISTRY, new ResourceLocation("tutorial", "tutorial_biome"));
public Main() {
IEventBus bus = FMLJavaModLoadingContext.get().getModEventBus();
bus.addListener(EventPriority.LOWEST, this::commonSetup);
}
public void commonSetup(FMLCommonSetupEvent e) {
e.enqueueWork(() -> {
BiomeManager.addBiome(BiomeType.COOL, new BiomeEntry(stony, 1));
BiomeDictionary.addTypes(stony, Type.SANDY);
}
);
}
}
And, Minecraft is now crashing with the errors:
1. java.lang.IllegalStateException: Unknown biome id emitted by layers: -1
Crash Report: https://pastebin.com/9nYUpA5v