Blackheart is a fictional demon appearing in the Marvel Comics universe, created by Ann Nocenti and John Romita, Jr., and first appeared in Daredevil (1st series) #270 (Sept. 1989). He is the "son" of Mephisto, and the archenemy of Ghost Rider. Fictional character biography Centuries of murder in a locale named Christ's Crown, New York, drew the attention of a demon-lord, Mephisto, who created a "son", Blackheart, from the energy of the accumulated evil. Blackheart explored the nature of evil under his father's tutelage, clashing with and failing to corrupt Daredevil and Spider-Man.Daredevil #270 Mephisto and Blackheart once tormented Daredevil, Brandy Ash, the genetically engineered Number Nine, and the Inhumans Gorgon, Karnak, and Ahura, manipulating their emotions and tricking them. They were soon drawn into hell for worse torments. Brandy Ash did not survive.Daredevil #278-282