Add the ability to create custom Underground Biomes
For this add the following
- ability to choose main filler block for underground biomes (blocks like rock, stone etc.)
- ability to set amount of vanilla and custom ore generation (amount of diamonds, gold, iron, coal etc)
- ability to set amount of cave generation underground
- ability to set amount of water / lava generation underground
- ability to set amount of underground structures that spawn (mineshafts, mushrooms, etc)
- ability to choose secondary filler blocks and amount of secondary filler blocks (dirt, gravel, etc.)
- ability to generate custom structures underground from templates.
Minecraft does not have any mechanic to define underground biomes by default. This means we would need to write a new concept of world generation system for Minecraft and ship it with mods that used underground biomes. This is out of scope of MCreator for now.