Avarrish was a demon from an unnamed region of Hell, he along with five other demons were granted access to Earth when several Hell-lords:Mephisto, Satan, Satannish, and Thog, plotted to invade the Earthly plane by distracting Doctor Strange while they broke through the barriers that separated the Earth from Hell. Their intent was to gain ultimate power and control over humanity. To fulfill this fiendish plot they allowed Avarrish, Fashima, Hyppokri, Puishannt, and Unnthinnk, to have more sway over mankind. It was later discovered that the demon Maya was Mephisto in disguise. This demonic gathering would come to be known as the Six-Fingered Hand.
Avarrish made a deal with a human mayor Isaac Christians, who promised to serve Avarrish in return for making the town of Christiansboro, Virgina, prosperous once again. Avarrish began to take control of Christiansboro's inhabitants, exerting more and more control over them over time. In order to taunt the Gargoyle, Avarrish placed Christians' soul in the Gargoyle's body and the Gargoyle's soul in Christians' body. Avarrish made another deal with the dying Dorothy Walker, who was promised youth and extended life if she would give up the soul of her daughter, Patsy Walker, who was a member of the Defenders known as Hellcat.
Upon Dorothy's death from natural causes, Avarrish sent Christians to retrieve Patsy, and Christians blew up Patsy's house, nearly killing the house keeper Dolly Donahue, in the explosion. Avarrish created an illusion that the house was still standing, but the Defenders, with Hellstorm, soon uncovered the illusion and traced Pasty back to Christianboro. After the Defenders fought Avarrish's demonic hordes and a transformed and possessed Hellcat, Pasty's soul reasserted itself and drove Avarrish from it. The town of Christianboro was released from the influence of Avarrish as well, but Christians remained in the Gargoyle's body christening himself the hero and joining the Defenders. The true Gargoyle would remain in Christians' human form for several more months, and would later attempt revenge on Christians and the Defenders. Avarrish's whereabouts remain a mystery to this date.