I'm an admittedly subpar crucible player and I finished it. Take a void fusion rifle into the the control playlist and have fun. Killing Xyor was a little challenging but I did it with one friend playing with me. The trick is to stay on the floor where Phogoth is chained to avoid extra ads being dumped in on you. If you try to ply from the raised platforms in the room, additional ads will continue to spawn in making it a lot tougher. After unchaining Phogoth, ignore him, and keep your eyes on the landing pad where the tomb ships drop in. Xyor arrives with the third ship. Being a defender Titan or having one with you really helps too. Good hunting!