Iron Man #21 was published by Marvel Comics on October 1, 2007, as part of a series that began in 2004. Charles Knauf and Daniel Knauf write, and art comes from Dean White, Gerald Parel and Roberto De La Torre. This 36-page issue features Iron Man, Dum Dum Dugan, Maria Hill, Mandarin and Graviton, among 11 characters cataloged on VerseDB.