Killled it 2 weeks ago with 2 tanks, 4 or 5 heals, 6 dps. I tanked it myself with a guildie and we kited the boss around the camp. When we got 6 stacks we tank swapped and the tank with the stacks ran towards the entrance (not to far tho) untill the stacks wear off and ran back again.
Boss died after 3 attempts. Just beware of the lag, its horrible with all the circles.