Catacombs and spider nests entrances sometime generate in rivers.
Wedge1453 opened this issue ยท 1 comments
Closing since this should be fixed as of recent versions. It's still possible for dungeons to generate in water, but they shouldn't generate in river and ocean biomes (at least, not vanilla biomes, anyway). I don't see a reason to prevent them from generating in water at all - it's janky, but kinda cool, lol.