Not quite positive sum, but there's a German board game called Max. Players cooperate to get a bird, a chipmunk and a mouse safely to a tree while a cat named

Not quite positive sum, but there's a German board game called Max. Players cooperate to get a bird, a chipmunk and a mouse safely to a tree while a cat named Max is chasing them. Players roll dice that decide how much the cat or other animals move, and they decide what order to move each, or whether to distract the cat with milk or catnip.