[Soapy]

Know No Pain is almost like having 20 Defense as a passive, except it gets multiplied by how many instances of damage someone deals, making it horribly effective against things like multi-round guns.. and that's not considering the Rage mechanic.

I'd suggest either making it block a certain amount of damage per round, simply lowering the reduction per rank to 2 (and doubling the Rage it gives you, maybe), or stop it from working from behind as it's quite easy to drop multihit physical damage down to the single digits.