Mountains & Gravelly Mountains use their 1.17.1 biome ID name

confirmed - they reverted the biome ID change

Can confirm.

Yeah, can confirm. I can see how they overlooked it but yeah, it needs to be changed for clarity.

A bunch of extreme hills sub-biomes were missed in the experimental snapshots and weren't renamed. I imagine we should report them separately if they don't get renamed along with the other extreme hills in the next snapshots, but I'll report them here for now, in case Mojang reads these comments.

• wooded_mountains -> wooded_hills

  • Currently, wooded_hills is the name of the now-unused hill variant of forests. The current wooded_hills should be renamed to forest_hills

• mountain_edge -> extreme_hill_edge

  • Unused biome, but it should be renamed for consistency. Despite being unused, it was already renamed back in 1.13 pre-release 5 along with the other extreme hills biomes.

• modified_gravelly_mountains -> modified_gravelly_hills

  • Now-unused biome, but it should be renamed for consistency.

• taiga_mountains -> extreme_taiga_hills

  • Now-unused modified variant of taiga, and unrelated to extreme hills, but it should probably be renamed to avoid people getting confused when using /locatebiome (same reason for the mountains -> extreme_hills rename)

Can confirm in 21w39a.