Berenguer was once upon a time a smart and powerful arrancar with his ability to transform things into something else and known for creating the halberd zanpakutos seen very regularly within Dante's army. However after being driven mad by the furies for punishment against trying to run away and the lost of his mask fragment has driven him insane, leaving him the title of the mad forger. Although still possessing all the skills required to use his powers, he now often refers to himself in the third person and has a sort of mad hunger to his tone.