Sacred Vengeance

(Libris Mortis: The Book of the Dead, page 30, DnD 3.5)

[Divine]

You can channel energy to deal extra damage against undead in melee.

Prerequisite

Ability to turn undead

Benefit

As a free action, spend one of your turn undead attempts to add 2d6 points of damage to all your successful melee attacks against undead until the end of the current round.