His first work was a title called Gore Shriek for a comic book store in Albany, New York. The book was specifically labeled Not Intended For Children because of the graphic content. For three years he worked with Marvel Comics on titles such as Quasar, X-Force and What If?,before he left to work for Todd McFarlane. Capullo did the cover of Spawn 26 first, then he became the main Spawn artist until issue 100. He has since been the main cover artist for the book. In THE SPAWNING GROUND section of Spawn # 50 Todd McFarlane credited Capullo for making the characters what they were and said that if he were to return to the book that he would emulate Capullo's style and persuade other artists to do so. He also created his own miniseries titled The Creech.