The Space Phantom by Alex Rodway
One of many advance scouts for the alien fleets controlled by Thanos, Phantomas Ectos, codenamed the Space Phantom, was granted time-manipulation technology by the interdimensional scholar Immortus that allowed him to shape-shift into a near duplicate of an individual and then warp space-time to shunt the individual to the Limbo dimension to make it seem as though nothing had ever happened while the hapless victim is studied by Immortus for usefulness in the future. This was done as part of an experiment to test such powers on a weaker individual and have it prove its mettle against the Avengers in battle so that Immortus can see just how powerful the hero team really is when confronted by an agent of the Dark Starfleet. Phantomas was given these powers with a false promise that his people would be freed from Limbo and be able to take control over the Earth as a new Planet Phantus.
Upon arriving to Earth through an interdimensional portal in space by assuming a meteor shape, the Space Phantom manipulated the New Avengers into nearly fighting one another by replacing each of them one at a time, but he didn't replace either the Black Widow or the Scarlet Witch due to his belief that female shapes were beneath his principles. This proved to be his downfall when the Scarlet Witch managed to use her psionic abilities to expose him, shunting him back to Limbo instead. Upon arriving, Space Phantom was punished by Immortus for his failure by being subjected to the dimension's eldritch energies, twisting and misshaping into a ghost of his former self, then was cloned/brainwashed in this form into an army of identical loyal followers to serve Immortus' goals rather than those of Thanos. The original Phantun race was eventually freed from Limbo by Thor using a long-forgotten temporal ability of Mjolnr for one time only.