holy crud i'm not the only person that likes Soul Knight here?!Definitely by far Gold Mask from Soul Knight.
His PKP attack is unfair high spread RNG bullet spam, and can't be interrupted by stun or freeze.
The debuff pools from the poop air strikes cover a huge part of the arena, and along with dealing damage, have a 100% chance to, when even barely walking into them, inflict the weary debuff, which cuts your attack speed in half.
The splitter cannon attack would be fine if he didn't shoot so many bullets at once and start using another attack before the bullets are gone.
And all this would be a lot more tolerable if he didn't constantly run around like he snorted his weight in cocaine before you fight him.