Avenging Echo is a 1st level avenger Encounter power that was introduced in the Player's Handbook 2.
Avenging Echo
Avenger Attack 1
Your weapon sweeps in a deadly arc, leaving in its wake swirling radiant energy that keeps foes at bay.
Standard Action
Melee Weapon
Target: One Creature
Attack: Wisdom Vs. AC
Hit: 1[W] + Wisdom modifier damage. Until the end of your next turn, any enemy that ends its turn adjacent to you or hits or misses you takes 5 radiant damage.
Censure of Retribution: The radiant damage equals 5 + your Intelligence modifier.