Wanted to farm the Mount, what I did is kill the group before the boss except the priest. He casts a spell that increases your damage by 100% for about 20sec. Steal, Sheep, Nuke, Loot.

You have to kill the boss before the adds shred you. Iceblock when combustion is active if needed...

I did screw up alot, (living bomb anyone?), but she died fast. You will probably do better ^^