Temple of Light is a 1st level avenger Daily power that was introduced in the Player's Handbook 2.
Temple of Light
Avenger Attack 1
Your weapon strike creates a field of searing energy around an enemy. The energy burns any foe you hit that is within the field.
Standard Action
Melee Weapon
Target: One creature
Attack: Wisdom vs. AC
Hit: 2[W] + Wisdom modifier radiant damage
Effect: The attack creates a zone of radiant energy in a burst 2 centered on the target. The zone lasts until the end of the encounter. When the target moves, the zone moves with it, remaining centered on it. Whenever you hit a creature that is within the zone, that attack deals 1d6 extra radiant damage.