Paul Duval was working as a lab technician when he spilled an experimental compound on his right hand. Learning he had gained the ability to turn himself into living stone, he terrorized New York City as the Grey Gargoyle. He was defeated by Thor after he tried to steal Mjolnir, believing it to be the source of Thor’s immortality. Since then, Grey Gargoyle has faced most of New York’s heroes but has been defeated each time.
The touch of Duval’s right palm can transform anyone or anything into immobile, granite-like stone. The transformation often lasts about one hour. By applying his palm to himself, Duval can transform into living stone, fully mobile, unlike his victims. His stone form is superhumanly strong and durable.