As you strike, your anger at your foe's attack on an ally manifests as baleful fire on your weapon.

Encounter   ✦     Fire, Martial, Weapon
Standard Action      Melee weapon

Target: One creature

Attack: Strength vs. AC

Hit: 2[W] + Strength modifier damage. If the target has hit an ally with an attack during this encounter, the attack deals fire damage equal to 3 + your Constitution modifier.

Published in Martial Power, page(s) 35.