I used to play a Matrix online game. When you were level 15 or so, which was super easy to get to, you were able to be killed by other members. So there was this group of high level guys who would terrorize everyone in the game. You would be halfway through a mission and they would show up and kill your whole party. Then you would have to restart the phase of the mission and it was enraging.
Then WoW came out and all of those guys started playing it instead. About a week later everyone left was just sitting around chatting in a central area. There was no fear, which seemed cool, but as time went on it got more and more boring. To save the game, I started killing everyone. I racked up the highest player kill count pretty quickly, and oddly enough everyone started respecting me. I made it clear that it was nothing personal, just business. So I would show up, they would run for their lives, and I would track them down. Sometimes I would spare them, other times I would kill them 30 times in a row. Then others joined in and the game became fun again.