Religion: Chitauri religion
Name: Greg (impostor)
Publisher(s): Pocket Star Books
First Appearance: The Ultimates: Against All Enemies (2007)
Creators: Alex Irvine
Super? (Has Super Powers/Special Abilities/Technology): Yes
Number of Appearances: 1
Note: posed as Hank Pym's technician to spy on him
Greg was an alien, one of the shape-shifting invaders known as the Chitauri. He was working as a technician and assistant for brilliant scientist Hank Pym. Pym was working on developing a way to use ants to detect the Chitauri.
Of course, Hank Pym did not know that Greg was a Chitauri. Presumably the original, real Greg had worked for Hank Pym for some time before being killed, devoured, assimilated and impersonated by a Chitauri spy.
Greg was present when Hank Pym first ran a test of his idea of using ants to detect Chitauri. The ants zeroed in on Greg, which Hank thought was a mistake - until he realized that Greg was actually a Chitauri. Exposed, the Chitauri "Greg" dropped the pretense of pretending to be human and started to transform into his real form. "Greg" battled Hank Pym, but Pym killed him.