When a purging wand is equipped by itself without a shield or another weapon, sucker punch shares the same number of charges as the number of charges on the wand and using sucker punch will deduct from the amount of charges left on the wand. When there are no charges left, sucker punch is no longer usable. Source vamp will still have the same number of charges it started out with when the wand was equipped if sucker punch is used to deduct charges from the wand. The number of uses available for source vamp will refresh once the wand is re-equipped if the charges are deducted through sucker punch.
