when we did gruul the mage kited the shaman så we could take down the preist and we had two tanks. one on gruul, and the other tank went for the warlock( shadow preist or whatever)
we had mostly melee dps and a few mages. this tactict worked quite good actualy! im suprised myself it worked:D

but i got the hammer of naaru so i was happy:D:D:D