It's in the title. There are quite a few feats in this game that suck, and a few that are broken. But I am talking about Kiai in particular, it is one of the most broken feats in the game's current state. As it stands, being put out of stamina is a near instant death sentence unless you play well and somehow not lose all your hp before your stamina comes back. Getting blinded is also a massive debuff, to be hit with, throwing you hard on the backfoot and is incredibly hard to fight whilst blind, so much so that they removed it from Raider's kit because it made him too powerful. So why is it that there exists a feat, that is low level, on a very short cooldown, that both blinds and drains ALL of someone's stamina, instantly, and is in an AOE?

Couple suggestions to fix the issue with just this feat:

Remove it from the game- less than ideal idea, but if it can't be balanced then get rid of it.

Make it single target- this would make it less a win button, but not solve the issue of it still being able to blend people, and most characters who have it use it one one person, since you don't need to save it for anything, its cooldown is so short.

Remove the blind- I honestly prefer this option in addition to a few other things, a skilled player can deal with not having stamina for a bit, but the blind makes it a bit excessive.

Drastically increase the cooldown- This needs to be done, but it won't likely fix the issue alone.

Make it not take ALL of someone's stamina- I am unsure of this one, it would depend on how much it got nerffed to.

Personally I think it should have its cooldown increased by a significant margin from what it is and the blind removed, but I wanted to lay out a few ideas of what they could try to do to possibly fix it, but it needs something done, the feat is so powerful. It is a neat idea in concept and I would like to see it stay in some form, but not what it is now, a button you push so you can spam someone to death with little chance of repercussion before you get a decent chunk of free damage.