Panther Style

(Style, Combat)
You can strike back at enemies who attack you when you move.
 

Prerequisites

Wisdom 13, Combat Reflexes, Improved Unarmed Strike.
 

Benefit

While using this style, when an opponent makes an attack of opportunity against you for moving through a threatened square, you can spend a Swift Action to make a retaliatory unarmed strike attack against that opponent. Your attack is resolved after the triggering attack of opportunity.
 

Combat Trick

If you have a Stamina pool, the following Combat Trick may be used with this feat.
  Whenever you provoke an attack of opportunity, you can spend 5 Stamina points to make a retaliatory strike as a Swift Action.