The Doppelganger began life as a living fractal, a geometric pattern in the Dimension of Manifestations, able to assume the forms and attributes of any being, real or abstract. When the mysterious Magus set out to obtain the vast power of the Infinity Gauntlet, he contracted the ruling fractal, Prime Manifester Anthropomorpho, to transform several young fractals into monstrous versions of Earth's super heroes; the Doppelganger was one such creation, based upon Spider-Man. It and its brethren were sent to Earth to attack the heroes in the so-called Infinity War. The Doppelganger interrupted a fight between Spider-Man and the Hobgoblin, who impaled the creature upon a fence.
Following the battle, the Doppelganger was retrieved by the demonic Demogoblin, who unknowingly infused it with supernatural energy, enabling it to remain in the Earth dimension following the Magus' defeat. Demogoblin directed the Doppelganger in a grudge against Hobgoblin, whom the altruistic Spider-Man protected. The foursome's fight brought them to another battle, where the supernatural heroes Ghost Rider and Blaze were fighting a group of demonic Deathspawn and Spider-Man's murderous nemesis Venom. Both the Doppelganger and Demogoblin were subsequently pulled underground by the Deathspawn, with two Deathspawn briefly taking up silent residence within the Doppelganger's body.
The disoriented Doppelganger wandered New York for days before being attacked by the psychotic Carnage, who mistook the creature for their mutual enemy Spider-Man; however, Carnage's companion, the equally insane Shriek, took a liking to the Doppelganger, and the deranged couple introduced their new "son" to the "pleasure" of random murder. During their spree, the three were joined by Demogoblin and Carrion (Malcolm McBride); they also fought Spider-Man, the Black Cat, Cloak and Dagger, Venom, Morbius, and others. The Doppelganger became devoted to Shriek; when Carnage attacked her for rebellious behavior, it sprang to her defense, but Carnage gutted it and kicked it to the street several stories below. Carnage and the others were defeated shortly afterward, but whether the Doppelganger was truly slain remains to be seen.