He has wrecked my Harbringer Witchblade in like 10 seconds…
And… I picked Solael as my witch god 
So I’ll drop this toon and wait for a nerf, this is NOT a regular campaign boss !
Ok I was a bit dramatic, the second try did it… It was pretty humiliating to run all over the room but I managed to shoot him dead.
He is pretty squishy I think 
Sounds like the new bosses require also some play skills on top of good build !
I just meet him again in Ultimate and still think something off with him. I almost had him the first time but get caught by the stuns and wrecked. my toon is a fire caster Purifier, not a tank, and was lvl 93 so didn’t have access to BiS yet - i can accept him not being invicible. that was his first death tough.
problem is when i returned to finish him, i just entered the room and the roof just felt on me (like twenty projectiles or something like that). Insta-death. I’m not even sure i even aggro him lol.
so i’m fine with Kymon and Korvaak and i think every boss in the xpac now that i’m used to them but Ramzul ? I never hated a boss so much since the three Stooges back in Vanilla (except he’s not a roguelike dungeon final boss)
That said, maybe it’s a bug and i’ll report it in bug section if it’s the case.