Nicked this fellow earlier. 85 Berserker tanked, AC at 3750. Max hit was 5746, average hit 2672. He casted some spell on ranger who seemed to take quite a big dent.. Also dropped a http://lucy.allakhazam.com/item.html?level=85&id=105876 (zonewide rare drop i guess)
Nothing too special about this guy. He's a cleric. Uses cleric pet hammer. He likes to Complete Heal and will GATE at low health so be ready for that. His DPS isn't much worse than the trash mobs.
He's immune to mez. I used pally stun AA to disrupt him. normal pally stuns didn't work.