Ok, so my linkshell was doing this today and we keep having to use a brew to kill 2 of them instead of straight tanking it, we have a stun order of 4 people that are stunning all spells, we tank it from behind just like strats ive seen say so breath doesn't hit you.
Plague swipe keeps taking all shadows and hitting for a ton of dmg, that part isn't what wipes us, that part is np, we just put shadows back up and cure.
But he builds resistance to stun after a while and then we can't stun spells anymore, thus he levels up.
What are we doing wrong?