D'Arby possesses the Stand named Osiris, which allows him to steal the souls of individuals who are defeated in gambling contests. He is known for his psychological tactics, reading opponents' reactions, and exploiting their weaknesses to gain an advantage. He derives pleasure from the suffering of others and exhibits a sadistic personality. D'Arby is eventually defeated by Jotaro Kujo in a high-stakes poker game, leading to the release of the souls he had stolen.