Oh, it gets way worse then that. I tried killing a Pech in a crowd of mobs and so many Mana Creepers went off it crashed the game instantly and deleted the save.AM2 just doesn't seem to get along with dimensional mods. I tried going to The Erebus and ended up drowning in dryads.
It's kinda sad, really. Can't even use that dimension at all due to this plus the stupid pixies causing a 40 FPS drop. What's more sad that the bug has gone unfixed since release, but that's another story,