Scoundrel's Luck (3.5e Maneuver)

Luck calls to luck, the gamblers say, and this maneuver lets you make it come true.

Any time you receive a maximum result on a damage roll until the beginning of your next turn, you may roll damage again, and add the second result to the original. If you roll maximum damage and the second roll, you may roll damage again, and so on. You may initiate this maneuver immediately after rolling maximum damage, in which case it still allows you to reroll it. This maneuver is a supernatural ability.