School divination
Casting Time 1 standard action
Range personal
Duration 1 round/level (D); see text
You open your mind to read the underlying probability of the universe. At any point during the duration of this spell, you can discharge it to reroll any d20 roll (attack roll, saving throw, skill check, etc.). This takes no action, but you must choose to do it before you learn the results of the first roll. You must take the result of the second roll, even if it is worse.