Gully had been interested in art but it was only when he was incarcerated that he had a Robert the Bruce moment with an insect that changed the direction of his life. According to Gully:

Ant was first picked up by Arcana Studios and later moved to Image Comics where it would deal with more adult themes, leading to an incident where Gully had to issue an apology for a partial nude scene. The comic book would move again to Big City Comics where three further issues were published.

Mario Gully later moved from the Independent pool of comics to go on and draw for Marvel Comics. He has drawn Marvel Illustrated: Treasure Island adapted by legendary writer Roy Thomas with whom he would also work on the adaptation of Kidnapped, Marvel Adventures Hulk, and Exiles.

Comics work includes:

• Ant #1-4 (script and art, Arcana Studios, May—October 2004)
• Ant #1-7 (script and art, Image Comics, August 2005 - June 2006, tpb Ant: Reality Bites collects Ant #1-4, 120 pages, April 2006, ISBN 1582405808)
• Ant Unleashed #1-6 (script and art, Big City Comics, December 2007 - May 2008)
• Totem #1-7 (pencils, with writer Jeff Kaufman, Big City Comics, 2007—2008)
• Marvel Illustrated: Treasure Island (pencils, with writer Roy Thomas, 6-issue limited series, Marvel Comics, August 2007 - January 2008)
• Hulk #6 (pencils, with writer Paul Benjamin, Marvel Comics, February 2008)
• "World Tour" (pencils, with Mike Raicht, in Exiles: Days of Then and Now, Marvel Comics, March 2008)
• Marvel Illustrated: Kidnapped (pencils, with writer Roy Thomas, 5-issue limited series, Marvel Comics, January—May 2009)
• Army of Darkness #24 (art, with writer Mike Raicht, Dynamite Entertainment, July 2009)

Interviews

• NEW-GEN Spotlight talks to Mario Gully