You boldly confront a nearby enemy, searing it with divine light if it ignores your challenge.

At-Will   ✦     Divine, Radiant
Minor Action      Close burst 5

Target: One creature in the burst

Effect: You mark the target. The mark lasts until you use this power again. The mark also ends at the end of your turn if you didn't engage the target, meaning you neither attacked it during your turn nor are adjacent to it at the end of your turn.
    Until the mark ends, the target takes radiant damage the first time each round when it targets any of your allies with an attack power that doesn't include you as a target. The damage equals 3 + your Charisma modifier.
    Level 11: 6 + your Charisma modifier radiant damage
    Level 21: 9 + your Charisma modifier radiant damage

Special: You can use this power only once per turn.

Update (11/17/2010)
The power has been revised for clarity and ease of use.

Published in Player's Handbook, page(s) 91.