EDIT: THE POST TITLE IS WRONG. I CANT CHANGE IT... It is not the enemy, it is my own warlocks.
I was playing Berbata (level 4 from Deeper Dungeons) with KeeperFX 0.42 and r753 nigthly build applied and I saw a strange behaviour. My own warlocks are killing me creatures on the library near the start of the level - imps and warlocks.
This is my savegame:
https://mega.co.nz/#!nc8l3QZL!GRBaZj...dGUmrtETBHvFuQ
If you load it you will hear the warlock attacking sound (the fire ball), sometimes he completely kills an imp, if not, loads again to see it. Also they attack another warlocks. Load the game and spend some seconds watching the library.
EDIT2: ALL THE IMPS YOU LEAVE IN THE LIBRARY, MY WARLOCKS ARE WILLING THEM. WHY?