Avenger Utility 16Battle Blessing
You have sworn that your enemy shall fall—and it will, by your or your ally’s hand.
Immediate Interrupt Close burst 5
Trigger: You or an ally within 5 squares of you makes an opportunity attack against your oath of enmity target
Effect: The opportunity attack deals 1[W] extra damage if it's a weapon attack, or 1d8 extra damage if it is not a weapon attack.
Changed in July 2012 rules update.
Published in Divine Power, page(s) 14.