With an instant of focus, you take careful aim at your foe and strike with the legendary accuracy of the elves.

Encounter  
Free Action      Personal

Trigger: You make an attack roll and dislike the result.

Effect: Reroll the attack roll. Use the second roll, even if it's lower.

Published in Player's Handbook, page(s) 40, Heroes of the Fallen Lands, page(s) 260.