Quote Originally Posted by Crimson-Falcon View Post
both are un-stunnable by the moment the add start casting it unless you missed wash word
no, he is correct, I can confirm dreadwash (unavoidable mass hysteria) is stunnable but dreadstorm (aoe hysteria) is not, when you try to stun dreadstorm you'll get a "Invulnerable" warning. Getting dreadwash stunned is much more important when the guard rails are down during the last 15% phase of the fight.

the easiest way to deal with that add is do it like dreadknights in T5, stunlock and burn it down. Only start stunning when it's below 80% health, too early and you'll end up getting resists, other melees should refrain from stunning until after the 3rd stun.