Haven't seen any in the mountains either, but maybe they do show up, but so far I haven't seen any. They are spawning in the meadows & black forest at night time for sure though, can confirm that much.

All but swamps.

this is certain?

It's directly from the game files.

Makes a serious swamp base a little more attractive. I've been intentionally delaying the last boss waiting for content , but seriously thinking about going to fight him tonight.... just cuz.

Thanks for the information, guess i'll be building a tree house in the swamps