Need Advice/Help

[Dashuto]

When I try to stun that move it says invulnerable. But when I try to stun again soon after it works, but by that time hysteria already prompt on the floor. Is there something I'm doing wrong because it happens everytime

Here's whats going on, once he begins casting those bad bad moves, he cannot be stunned.

You have 3 actions from him until he begins casting Dreadcrap. He is meant to be stunned BEFORE he casts Dread/Dark moves. Once he begins casting that horrible stuff you are too late.

Here is my strat:

I usually just let him run to a dps and make sure no one is trying to fluid aura him. (Some people flash him and hold at edge, you can do this too especially if you think he'll live. Stop flashing when its close to STUN time)

I watch him.... Ruin. Ruin. Ruin.<-- NOW YOU STUN. Do not spam it.

Stun once, 4-6 seconds.

Stun again as it wears, 2-3 seconds.

Stun again, 1 second.

Now you've done all you could, hit your off GCD's if you havent, start smacking him, pray someone pushes him, or that the DPS are not sucky and he dies by now. This is the strat.