Another trick is when you see Qodrons eye shoot his head off. Then he'll come to you so you don't have to risk getting your head blown off by snipers while trying to take him out. Warlock with self-res on the team is good for emergencies. It's is good to assign one person to hunt the eye. while the others hit boss and annoying snipers. Also the enemies spawn based on you damaging the boss. so another tactic is to ignore the boss and clear the enemies out then everyone concentrate of doing damage to him. Another wave of enemies will spawn clear them out and repeat. Edit: If you don't have a warlock and keep getting wiped by the shields, it might pay to leave a teammate dead ready for revival. Then when the shields come up you can revive them and they won't have a shield around them so they'll live and stop the team wiping.