wolf spawning conditions weren't updated to 1.20.5, making 3 wolf variants unobtainable

[shinevee]

also the sparse_jungle doesn't generate, which is where one of the wolf variants spawns, meaning even if you do fix wolf spawning for the savana_plateau and wooded_badlands, the "rusty" wolf variant would still be unobtainable, thus simultaneously making the advancement "The Whole Pack" unobtainable.

[Crystalis7]

Thank you for raising. On the note of the Sparse Jungle, this has been replaced with the Rainforest biome, and so I will likely allow for the 'Rusty' wolf variant to spawn there instead. Will address in the next minor patch.