Luck Devotion( Complete Champion, p. 61)
Luck makes your attacks more effective.
Once per day as a swift action, you can activate this ability to improve your combat prowess. For 1 minute, if the result of any damage roll you make is below average, you can increase it to one-half the maximum possible (rounded up). This effect works for all damage you deal, whether from physical or magical attacks.
You can select this feat multiple times, gaining one additional daily use each time you take it.|||If you have the ability to turn or rebuke undead, you gain one additional daily use of this feat for each three daily turn or rebuke uses you expend.