Hello there,

this is my first ever bug report (ever), if I have left out needed information, please tell me right away.

I was trying to add as many compatible worldgen and biome mods as possible, I've added right below the

• modlist.txt:
  modlist.txt

• latest.log (with all mods, had to kill the idling game via the terminal to retain the log with crash-assistant):
  latest.log

• JVM Dump (shows the Server thread in a TIMED_WAITING (parking) state while "worldgen" is stuck at 0%, obtained via jstack [pid] > dump.txt):
  dump.txt

I know that it is a lot of mods, but if I remove "Oh The Biomes We've Gone" it all works flawlessly. I can alternatively remove C2ME, Terralith, CliffTree and sometimes "Biomes O Plenty" and then it'll work with "Oh The Biomes We've Got".
"Oh The Biomes We've Got" did not work in combination with "Biomes O Plenty" yesterday, but does today for an to me inexplicable reason.

The single common denominator is a "Feature order cycle" issue, here's some excerpts of a few different runs today, I kept removing one mod at a time until worldgen worked:
log excerpts.txt

Feature order cycle found, involved sources: [Reference{ResourceKey[minecraft:worldgen/biome / terralith:siberian_grove]=net.minecraft.class_1959@

This is an incompatibility with us and Terralith

Fixed in commit referenced above