Knockdown, Blind, Stun, Frozen, Petrify, are all status effects that completely inhibit an enemy from attacking. Avoid those ones.
Stun is better because it's only a 100% chance to stun if an enemy is standing on blood or water and you cast lightning on that surface.
CC is fine though. You have to be able to CC some of the mobs on higher difficulties to survive. Without CC you'd be toast. I dont' see how that's overpowered, but is a normal part of these kind of games... Am I wrong?
I just want to know the top major game breaking skills whether they are broken on their own or only in combination with other skills, like Lone Wolf + Glass Cannon. Both probably fine on their own, but together break the game.