to pull a griefer is to become pissed at something that has little to no actual need which will lead you to eventuallyleaving a certain group (clan) for no certain reason.
While I was just minding my own business and picking up some herbs, this fucking griefer came out of nowhere and killed me. Then, I killed him 5 times and I'm going to kill him until he parlays or leaves the session, or till I get bored because I am griefing a griefer!