Extended Biome ID

Extended biome IDs are identifiers that allow for one biome to have multiple variants. These can be created by fractal biome providers and are fully utilized by forced height chunk providers (early and major release). They consist of three parts: the base ID which refers to the biome the extended ID is based off of, the variant which is the sub type of the biome and the weak marker which, when enabled, allows for a sort of wildcard comparison between other IDs.

The syntax of extended biome IDs is base*variant. The variant can be ommitted with the syntax simply being the same as a regular identifier. If a tilde (~) is added at the beginning of the extended ID before the base ID, it marks the extended ID as weak which causes the ID to ignore variants on equivalence checks. For example, minecraft:taiga*hills and minecraft:taiga*mountains are not considered equal but ~minecraft:taiga is considered equal to minecraft:taiga, minecraft:taiga*hills, minecraft:taiga*mountains and so on, but not equal to minecraft:snowy_taiga and other extended IDs with differing base IDs.