That made us think about all the stuff we do in-game that kind of makes us...well, bad guys, for lack of a better term, and we started wondering -- what's the worst thing that player characters have done (or been asked to do)? Setting Teron Gorefiend loose has to rank pretty high up there. Then there's that torture quest out in Borean Tundra, which squicks people to this day. While we're on the subject of Borean Tundra, nobody particularly liked thinking about a daily quest offered in Coldarra, or the ugly results of Horde questing in Howling Fjord. If you wanted to look at the whole "player evil" thing from a larger perspective, you can even make a case that player-generated PvP is, within the context of WoW's lore, one of the more significant contributions to faction antagonism and war.
So what's the worst thing that your character has done -- or, failing that, the thing that you still feel the worst about? I've already got my pick.