Crown of Light is a 13th level cleric Encounter attack that was introduced in Divine Power.
Crown of Light
Cleric Attack 13
Blazing light coalesces over your ally to form a crown whose radiance pierces surrounding foes.
Ranged 10
Target: One ally
Effect: Until the end of your next turn, the primary target gains a power bonus to all defenses equal to your Charisma modifier. Make a secondary attack that is an area burst 1 centered on the primary target.
Secondary Target: Each enemy in burst
Attack: Wisdom vs. Reflex
Hit: 3d6 + Wisdom modifier radiant damage.