Add management mostly. So I would suggest using the tactic where the offtank handles all the adds and the others focus on the boss. So basicly the same positioning as last time, but with the offtank where the hunter at range used to be. The adds do minimal melee damage, and the debuff they do on their target causes and aoe damage effect (oh noes, I'm a tank, no ones around and I take 10K dmg -> shrug). Might work, might fail epically, but only the future can point that out. The parasites might spawn more adds, but even so... We'll see if I can handle them, if not quite, one dps can help me out.
Ordo Malificum