Well what we did was enter the room we all fire snipers and rockets from across the room at him.... When he rotates we move along the top to the other side all 3 focusing on getting cover and clearing adds along the way... We repeat snipers and rockets... He rotates we rotate keep in mind my team always has defender Titan for a bubble for cover. It's not hard if you have a team that works and moves as a unit not a bunch of solo heroes