Arcane Performer

You depend upon your performance ability to aid in the casting of spells.
Prerequisite: Ability to cast arcane spells without preparation, Perform 1 rank.
Effect: In order to cast any spell, you must succeed at a Perform check (DC 10 + spell level). If you fail, you lose the spell.
Suggested Class/Race: Bards
Source:Dragon Magazine #324 (Class Acts - Flaws For Bards)