Ah, I should have clarified a few things about that: 1. That was only the very edge of a group and I never saw the other side, nor was I able to find a way around them. 2. That was the thinnest group I saw, and the only one i was able to actually get a screen shot without getting them immediately trying to swarm me. 3. These groups are showing up every time I go inside and wait somewhere for a few game hours. I know I am not being followed by them either since I always watch my back and never just go in a straight line. On a different note, one group was so dense that I couldn't see the ground tiles under it, and when they all came to kill me the game didn't lag. So, I guess there is that.