A feat for Thieves:
Painful Strike
Your attack causes your opponent intense agony.
Prerequisites
Str 13, Power Attack, Backstab
Benefit: By opting to reduce the damage dealt by your backstab, you can strike to cause you target intense, throbbing pain. This pain imposes a temporary penalty to attack rolls. This feat only affects creatures able to feel pain.
(Adapted from the feat 'Painful Strike' in Dragon Magazine #344)
Painful Strike
Painful Strike
Proud member of the Order of the Deinonychus Claw