If you possess 425 Archaeology and a Troll Tablet, you can buff your group with Call of the Raptor, a spell (which persists through death) that occasionally summons raptor hatchlings to attack your enemies. The raptor-lings cast "Tiny Rend" which stacks up to 5 times (over all the raptors, I believe--ie, you can't have 3 different stacks of 5; it's just 1 stack of 5 which stacks very fast) and does a moderate amount of damage.
As a medium dps fury warrior--pulling anywhere from 10 to 20k, averaging about 14k--the raptor did 1.5-2% of my damage. Over the course of the instance I had done about ~40 million damage, and it did a bit under a million damage with it's Tiny Rend. Multiply that by 5 group members and you might have around four million damage (almost as much health as some of the bosses!)