Centuries of murder saturated the Christ's Crown area with evil until the attempted rape of a young girl named Sarah drew Mephisto to create a “son”, Blackheart, from the accumulated wrongs. Slaying both rapist and victim, Blackheart explored the nature of evil under his father's tutelage, clashing with and failing to corrupt Daredevil and Spider-Man. Mephisto and Blackheart soon drew Daredevil, Brandy Ash, the genetically engineered Number Nine, and Inhumans Gorgon, Karnak, and Ahura into Hell.
Observing these mortals led Blackheart to rebel against his father and seek a newer form of evil; in retaliation, Mephisto diminished Blackheart’s powers. Focusing on those who walked the line between good and evil, Blackheart tried and failed to recruit Wolverine (Logan), the Punisher (Frank Castle) and the Ghost Rider (Daniel Ketch) to his rebellion. Blackheart also aided Wonder Man against Mephisto and helped Misha of the mercenary Warheads as her telepathic “Voice”, using Mys-Tech’s Rathcoole to obtain a mystic sword which could harm Mephisto. Returning to Christ’s Crown, Blackheart altered his followers into the Corrupt, and employed Wolverine, Punisher, and Ghost Rider as a feint to allow him to anoint the sword with an innocent’s blood. He apparently slew Mephisto, banishing his “father” from Hell and restoring his own powers to full strength. As Hell’s ruler, Blackheart focused on corrupting the Ghost Rider, aiding the Furies to possess mortal bodies to torment Ghost Rider (Noble Kale) and resurrecting the Scarecrow (Ebenezer Laughton) to send after Ketch. From his palace in the Burning Flesh district, Blackheart created his own Spirits of Vengeance: his consort Black Rose (the deceased Roxanne Simpson, ex-wife of Dan Ketch’s brother, Johnny Blaze), Verminus Rex (a spirit who had battled the Ghost Rider during World War I), Wallow (a homicidal mortal suicide whom Ghost Rider had thwarted), Doghead (a downtrodden immigrant), and Pao Fu (who had died in the arms of Ghost Rider as he tried to save her). Blackheart bargained to free Ghost Rider’s relatives from their curse; in return, Ghost Rider agreed to lead Blackheart’s Spirits. However, the pair fell out and Ghost Rider destroyed Blackheart, banishing him from Hell.
While ruler of Hell, Blackheart had tormented the soul of the mutant Stryfe by manipulating the X-Force group, which attracted the attention of the mutant sorceress Selene. After banishment from Hell, Blackheart allied with Selene as the Hellfire Club's temporary Black King. After defeating Selene's enemy Alyssa Moy, Blackheart battled the Fantastic Four, Mechamage, Hellstorm, and Margali Szardos; they ultimately defeated Blackheart, binding him beneath New York's Hellfire Club. Trapped there, he continued to aid Selene, opposing X-Force in an attempt to corrupt Sunspot, while awaiting his inevitable release.