One use only. When an enemy spell has been cast, a wizard who has a dispel scroll can read it instead of attempting to dispel the spell by using dispel dice. This automatically dispels the enemy spell; no dice roll is required. Note that even a dispel scroll will not help if the spell has been cast with irresistible force. Note also that a dispel scroll cannot be used to dispel spells that remain in play other than at the moment they are cast.