I am really unsure of implementing a Karma system. It seems to go against the game's core concept. The game was founded on the idea of lawlessness; you're a PMC cut off from your contractor, it seems to me a person like that would just be doing whatever it takes to make some money and leave. I don't mean to be shortsighted, but I think that in a way, all of the players are Scavs themselves, just trying to fight their way out of an everlasting conflict. I really don't see how a karma system would reflect those values. The only other men you should trust are your closest mates, both hypothetically in this scenario, and in reality. (The people you'd be playing with.) I could see a bounty system, but I figure it would be difficult to implement. Perhaps if your character always spawned with dog tags containing your username, and if your username was printed on the sleeve of your shirt, would people be able to distinguish who is who. Bounties could be issued for killing faction mates; that seems like a realistic approach to handling KOS behavior. KOS will always exist, and it is not necessarily a bad thing in this scene. There should be a reward for stopping it, not a penalty for doing it. If there is a bounty on your head, it should be communicated to the traders, so that most of them wouldn't trade with you. Bounties could be run through the traders so that people with bounties on their heads cannot redeem other bounties. (As to only provide the bonuses to non-KOS'ers.) Bounties would really only be issued for extreme cases, such as: A BEAR killing five other BEARs in one session as to adhere to the values of EFT.