Refusing the result that fate has decreed for you, you invoke stars of chaos and uncertainty and try to rewrite what has been written.

Daily   ✦     Arcane
Free Action      Personal

Trigger: You make a roll you dislike

Effect: Reroll the attack roll, skill check, ability check, or saving throw, using the higher of the two results.

Published in Player's Handbook, page(s) 134, Class Compendium.