Some mods that add biomes can mess up world-gen if you add them post world, if I remember correctly. It's something about biome-IDs being swapped around, but its not a guaranteed thing. I'm not like, 100% sure if its just a constant thing from biome mods that can't be helped (not the best coder here) but would adding this to a 1.18 world potentially mess up any generation, such as chunk errors where biomes like, stop? Sorry if this is solely issues, wasn't sure where to ask this.