Shattered Kingdoms

Self defense determines the chance to hit with unarmed attacks, the other two unarmed skills do not. Self defense also allows you to use regular knuckles.

Brawling increases damage and adds a second attack, and allows you to use spiked knuckles.

Wild fighting increases damage again, adds a third attack, allows for the use of claw weapons, and makes you hard to be parried while unarmed.