Thanks for the replies guys we did it in the end I used vision of confluence black hammer and Gally. Blackhammer is an absolute beast!!

I use Sunsinger with radient skin. Makes my warlock a tank! I can take so much more damage.

Use a titan with armor of light. Titans and warlocks can just fly. Hunters use triple jump.

It's ok guys we've done it, two titans and a hunter.

Play it[spoiler]duh[/spoiler]

We went all the way to the left and crowded around the red barrel-like thing. We would pop out and shoot the boss as much as we could. Whenever the boss would summon his rage, our Titan would pop his bubble and we would jump out of the top and then back into the bubble so that we would only lose the extra blue health. Keep doing this until his rage ends (the ceiling should protect you from being shot while you jump). Immediately after rage ended, our Hunter made orbs for our Titan to build his bubble back up for the next run. Rinse and repeat. I used Fatebringer, Black Hammer, and Gjallerhorn. Good luck!!! Note: If you don't have a bubble Titan, try to jump up and down the staircase and find ways to increase your air time as much as possible. Having a self-res Warlock also helps save from a wipe too.