My solution was to load up on PvP armor. Everyone having 12k HP and at least 250 resilience made the fight much easier. Kinda redundant to do though, as by that point anything that drops is just going to get sharded. I also found it helpful to pull him to the South East corner of the room and keep everyone relatively close together so that his aggro dump thunderclap doesn't leave him whipping up on the softies.