I know I am necroing this thread but it really helped me beat this thing. lvl 12 and it was giving me hell until I used the buffs recommended here should have paid attention to the debuffs screwing me over. Lots of great advice here especially knocking the sob down with prone skills and debuffing the hell out of it first.
I few more spells that really helped a ton from my priest was keeping buffs up with the increase buff duration 2 times during fight and making sure u reapply the immunity to fear skill. I had 3 druids built for rotting skulls, priest built for damage and long duration buffs, a great tank, and a chanter which was awesome for paralyzing and giving my guys positive buffs. I completely wrecked it first try after reading this thread but had many attempts trying to work things out before hand sow as very familiar.
I used lots of pierce, crush, corrosive, and prone skills from druids. I would have turned on rotting skulls if I had time =) This was a fun and challenging fight to learn.