Tyranny commands. Make his life miserable. !mute, !burn, !gib, !disorient, etc... I wrote a LUA script that I won't share here that is an auto-bot against trouble players - that way we can go about our business and play and the troll won't even be able to join a team. Can't hack if you can't play! Eventually they get tired of being ignored and not being able to do anything and leave on their own.