Just thought I'd share my simple, but boring strategy for beating the dungeons. It came about because I simply couldn't kill the buggers do I wondered if I could employ the same technique.

Using a Golden Son assassin you simply keep using immortality, which means your team won't die. You can the chip away at the enemy until they are nearly dead, (on the assassin dungeon in particular) they eventually don't have any shield and you can kill them. I have a troll with cyclone talisman and if you get the shield they even kill themselves.

As I don't t seem to be able to get any too soon upto 5* this is the only way I can beat these. As I say boring but it works ☺️

YP