Commands API Auto Texture and Model Loading System (textures-api-v1) Undeprecated Choco's Atlas API More Lifecycle Events
Improvements to chunkgenerator#getMinSpawnY or whatever the method is called usages
Add a getMinSpawnY method to chunk generators because our previous changes just weren't enough for minecraft to be nice.
Chunk Generators can now use the power move of changing how the player spawns in them. (only in Dimensions that don't manually override method_1770 i.e. isValidSpawnPos. In vanilla, this is only the overworld generator).
Modded Dimensions can ignore this, as you can just override Dimension.1770, however, this is very useful for modded overworld generators.
If you are adding your chunk generator with a mixin to Dimension#createLevelSource, see world type api's MixinDimension to see how to enable functionality for your code by setting the internal api field.