How in the hell has anyone beat him? He was the second boss for my group when we tried PoE 32 last night, and it seemed like every time we took his shield down, he regened it to a different damage type. And then all the other cabal seemed to just keep spawning at a ridiculous rate and had so much health... Anyone have advice on how to beat him? Apparently the Gjallarhorn is a must have for this...