modlist.txt

It might be a problem of the mod not being compatible with Alex's Caves, or any other terrain gen mod I'm using (I'll provide the modlist) but the ones that I think may be a problem are: Terralith, Tectonic, Continetns, Yung's Cave Biomes. This is the Strongholf inside of Candy Cavity biome:

IDAS has a similar problem, Ill open an issue at IDAS's Github.