If your going to do anyhting more than a beatdown, including mayhem (unnecessary shit like breaking fingers on purpose, bashing head off ground, etc etc) you're in for a rude fucking awakening.

If I were to ever pull a knife, gun, or anything on somebody I'd kill them and everyone who witnessed it. Don't take chances, and don't fuck up. Don't take this message as advice to kill somebody cause that's just fucking stupid, but if you're going to do something bad, make sure you're not getting caught.

Best way to get him back would be screw him over completly using the legal system. :-D Plant some drugs, weapons, and other things in his car/house/personal belongings and give him 10 to 15 in a federal prison for it.