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With deft reflexes, you capitalize on opponents' mistakes.
Prerequisites: Dex 18, Combat Reflexes, Improved Unarmed Strike, Weapon Focus (unarmed strike); base attack bonus +16 or brawler level 12th.
Benefit: Once per round, when you are fighting unarmed with both hands free and an opponent misses you with a melee attack, the opponent provokes an attack of opportunity from you. You must use an unarmed strike for this attack of opportunity.