Alan Moore is a comic book writer, famed for such works as V for Vendetta, Watchmen, and Lost Girls. His series The League of Extraordinary Gentlemen contains at least two cameos by John Carter. The first is in the supplemental story Allan and the Sundered Veil, included in Volume One of the series, in which the series' protagonist, Allan Quartermain, encounters Carter and his supposed great nephew Randolph Carter (created by H.P. Lovecraft), as well as the Time Traveller (from the H.G. Wells book of the same name.) Carter has ended up in the same place as Quartermain during the near-death experience that first brought him to Mars in the beginning of A Princess of Mars. Together, these four face off against Wells' Morlocks.

O'Neill Carter

John Carter in The League of Extraordinary Gentlemen, Volume II (Kevin O'Neill)

The second appearance is at the very beginning of Volume Two, which coincides with Dejah Thoris' imprisonment at the end of The Gods of Mars. In this instance, Carter has been forced to abandon his search for his beloved princess in order to lead the Tharks in an offensive (alongside Edwin Arnold's hero Gulliver Jones and his Hither allies) against the "Molluscs" (the alien invaders from War of the Worlds, here presented as invaders of Mars.) Artist Kevin O'Neill takes several liberties with regards to Burroughs' creations; O'Neill's rendition of Carter has a mustache and beard and wears a Victorian-style uniform and helmet. The thoats, meanwhile, are depicted as entirely black with spider-like legs.

One of Burroughs' Green Martians also appears in Alan Moore's humorous fantasy mini-series Smax.