Born within the abstract entity Eternity, Abraxas was kept in check throughout the Multiverse by the existence of Galactus. With the death of Galactus on Earth-616, Abraxas was free to roam the dimensions, killing every version of Galactus he found. Abraxas sent a decapitated Galactus skull stored with an alternate earth Nova hurtling towards Earth. While Abraxas drew nearer, the walls of dimensional space began to blur, rendering Uatu The Watcher comatose and causing a group of other-dimensional super humans called the Law Enforcement Squad to enter Earth-616 and battle the Fantastic Four. Joining a group of cosmic heroes, the Fantastic Four battled a cadre of Abraxas' followers on the moon; the Silver Surfer was killed. Realizing the danger Abraxas posed, the Fantastic Four went on a dimension-hopping journey to recover the Ultimate Nullifier, the one weapon that could destroy him. The Invisible Woman found herself on Earth-1116 (Atlanterra), a world ruled by Atlantis; Mister Fantastic on Earth-11113, a world resembling the 1930s where he teamed with the heroic Five for the Future; and the Thing on Earth-111, where he met the Challengers of Doom before their world was devoured by Galactus.
While the Fantastic Four were away, Abraxas stalked Franklin Richards, who had foreseen his arrival in dreams. Franklin and his sister, Valeria, were teleported away by Roma. During this time, Abraxas encountered Namorita and transformed her into a Kymaera Atlantean state, making her unable to breathe oxygen and effectively killing her. Having each learned a portion of the location of the Nullifier from alternate world Johnny Storms, the Fantastic Four enabled the Earth-616 Human Torch to remember the location of the Nullifier. Nova then turned on the Torch, stealing the Nullifier for Abraxas, her true master. Abraxas then appeared to Roma and appeared to kill her.
Teleporting Valeria, Franklin, Roma's aide Saturnyne, and himself to the location of the Fantastic Four, Abraxas received the Nullifier from Nova. She revealed that in her dimension, Galactus took her as his herald-but still consumed the Earth. Nova was joined by a small army of her alternate selves to protect Abraxas from the Earth's heroes. Franklin and Valeria combined their powers to resurrect the Earth-616 Galactus, who easily retrieved the Nullifier and handed it to Reed Richards. Reed nullified the universe itself. The universe restored itself to its previous normality, with Abraxas nowhere to be found. The Silver Surfer and Namorita were returned to life.
Powers & Abilities
As antithesis to the cosmic entity Eternity, Abraxas is a powerful intelligence representing the embodiment of the destruction of the universe, and as such is far removed from the limits of human understanding. Presumably, Abraxas' humanoid form is a manifestation used to communicate, or is merely the perception of the individual witnessing his presence. His powers are limitless, and he can manipulate the fabric of reality to accomplish his ends.