Oh boy. You're doing the Luther Black fight all wrong.
The trick is that nobody touches Luther Black at all. The more you tick him off, the more he spawns monsters and the more he starts buffing them. You, as the tanker, want to hit him just once, and then kite him around like a Benny Hill flick while tanking and DPSing whatever uglies he summons that are biggest (his buffs increase the size and damage of his minions, but NOT their HP - kill the biggest ones quick or they'll overwhelm you).
You don't even need to lay a finger on Luther himself after the first hit, unless he starts directly attacking the Demon Key (which he shouldn't so long as nobody else touches him). Once the Demon Key unlocks the last of Luther's boxes, Luther's done; regardless of how much health he has left, the fight's over and you win.
Took a few face plants to figure out this easy way.
NOTE: I soloed this arc. Fun stuff.
First time, got into the room, Demon key starts to do his time, the bugger taking his sweet arse time, while I decided to try and smash Luther Black. Got him down to 1/3 third he spawns a villian Trey King melee. Meh, no big deal I think. I keep smashing, he spawns another one, and buffs the first one. Still no bigg deal. But more I beat on him the more he buffs and heal the things he spawned. It got to a point where there was four giant trey Kings smashing my brains in and the demon key taking his sweet ass time. Anyways, was doing well until the bugger got too close to a trey king and murked him before I could even get to him. Failed.
Second time, Beat on Black, ignored him, beat up the trey kings that spawned, they got best of me that round, failed.
Third time, decided to go back to first method, demon key got smashed when he had only 10% on the last glowie he had to visit. Failed.
Fourth time, hit black once, ran arond the room, shooting him just enough to keep attention on me, while demon key did his thing, demon key got stuck. Had to reset, failed.
4.5-(didnt reset entire arc)-same thing, demon key got stuck again, had to reset. ran out of patience. Ended. Failed.
5th time- alright, I got this Black guy, that sorry excuse of a ghost is doing his thing, going well, lose connection. IP having issues in the area as apparently according to them, someone boloed the area hub or as they said, blew it up. How do you blow up an internet hub? smh. Didnt get connection back until next day.
6th time-got black, got good connection, new hub i nthe area, nothing else could stop me, but was hoping that the d.key dont get stuck. Nope! He didnt get stuck this time...but got called away for emergency. Spent all day and night in ER with baby and the mother. Got back was too tired to log on.
Today, hopefully the 7th time is the charm. Hopefully nothing else happens and I can add this arc in the "done it" section.
Is it different with a team? Although I will not do any of those arcs with a team as I now lack the patience and will power to deal with other people's version of fun now (must be the old age kicking in), I am curious though as I heard some are a bit more "interesting" with a team and mob interaction.