Demon Infighting is one of a marines most useful weapons when running low on health or ammo. Luring zombies and demons to fight each other give you time to get heath, ammo, avoid an ambush, or you could be really creative and wipe out two or more baddies with a well placed BFG 9000 shot. Fun, huh? Making enemies go berserk however, is easier said then done. Some will easilly leap at fellow freaks when hit by them. Others will ignore it, pretend it never happened, and still try to brain you. Heres an example, your trapped in a long, narrow hallway, on either side of you is a Imp firing non-stop fire balls at you. All you have to do is step slightly away from the incoming fireball, causing it to hit the Imp behind you. If you're lucky the injured Imp will walk right past you, and head toward the other Imp. Giving you time to go get some supplies, or watch. About eighty-five percent of the time, you'll have to kill the survivor. Normally they'll be weak, and injured, leaving little work for you.