For me, the only reason I've been shot so far is because I try to work with others. I ask if the other person is friendly, and they say they are; then when I let my guard down, I get shot. Right now, the mod appears to be PvP + zombies. There's virtually no reason to not shoot another player on sight. There needs to be some purpose to working with others. Perhaps if something was added to give bonuses to groups of players that solo players won't get(more loot from clearing a town? Where 2 players would get >2x the amount of loot as a single player.This would be tough to implement though...), it'd give a reason for people to work together. Some of the ideas that others have come up with here would work too, but there needs to be an incentive to work with others, which atm this mod lacks.