M. Rex is a title by Avalon Comics, a subsidiary of Image Comics. It ran for two issues in 1999. The series later served as a basis for Man of Action to create Generator Rex.
After successfully escaping from Sarragasso Sapphire to his and Rex's hideout in Nevada, Spilken can't help but blame Rex for their failure. Fearing the Sheik's wrath and possible revelation which might come later from the data he left behind along with Rex, Spilken makes a decision to "vanish" without a trace. As he is about to leave the hideout he meets Rex, who's safe and sound. It appears that he'd escaped from the ship on a weird spider-like flying device created with his nanites. Rex, not suspecting he was about to be abandoned, happily hugs his guardian and explains the mystery behind the build he made of "thin air". Spilken sees amazing new possibilities he can achieve with Rex's unique abilities and powers.