Banished Cells I:
So on this one the final boss has a one shot mechanic called soul blast. Normally this wouldn't be an issue in most dungeons because the tank can handle it or there's a warning. But this hits anyone randomly at anytime and has a very short animation. The only way to avoid it is to block or dodge roll otherwise it instantly kills you. But with the short animation there's barely any time to react and no time to call it out. So everyone constantly dies.
For this boss I think he should have a 2 second build up time before casting soul blast.

Direfrost Keep:
The final boss for this one heals way too much.
So obviously you're supposed to break free as soon as possible but, because the game is so laggy, for me and everyone I've talked to it takes 5+ attempts at spamming both triggers to break free from anything even though we have enough stamina to do it.
Other then that the boss does it constantly and seems to be able to heal from 90% health back to 100% in less then a second. I tried using dark flair to reduce the healing but it didn't seem to make a difference.
For this boss I feel like I'm missing some sort of mechanic.

So I could be missing mechanics and would like to know how to properly do these. It's hard to notice mechanics before when the boss would just melt because they never had a vet difficulty. The groups I ran these with were randoms that gave up on the first try without trying to figure out how to do it and had bad dps(I was healing these).

So far these are the only dungeons I've done and had issues with so I'll update if I come across anything else.