Needs review
Source: Complete Warrior

Description: You can bellow forth a shout that strikes terror into your enemies.

Prerequisites: CHA 13, Base Attack Bonus +1

Required for: Greater Kiai Shout

Making a Kiai shout is a standard action. Opponents who hear you and are within 30 feet may become shaken for 1d6 rounds. the Kiai shout affects only opponents with fewer Hit Dice or levels than you have. An opponent in the affected area can resist the effect with a successful Will save (DC 10 + 1/2 your character level + your Cha modifier). You can use the benefit of this feat three times per day.