Deafening Strike
(Complete Scoundrel, page 76, DnD 3.5)
[Ambush]
Your stealthy attack leaves your foe's head ringing.
Benefit
Your successful sneak attack causes the target to be deafened for 3 rounds. If you use this feat a second time on a target before 3 rounds have elapsed, the effect of the first use expires. Using this feat reduces your sneak attack damage by 3d6.