Favored Power Attack [General]

You are able to deal more damage against your favored enemies.

Prerequisites: Favored enemy ability, Power Attack, base attack bonus +4.

Benefit: When you use the Power Attack feat against a favored enemy, you may subtract a number from your melee attack rolls and add twice that number to your melee damage rolls. If you attack with a weapon in two hands, add three times the number. The normal restrictions of the Power Attack feat apply.

Source: Complete Warrior, page 98.