Mephisto

Few villains in the Marvel Universe cast as long a shadow as Mephisto, who burst onto the scene in 1975's Fantastic Four #157 — a Bronze Age debut courtesy of Roy Thomas and Rich Buckler that launched one of comics' most enduring presences. Over five decades and 254 catalogued appearances, this infernal schemer has haunted some of Marvel's greatest heroes, sharing pages with Spider-Man, Thor, Captain America, Stephen Strange, and Peter Parker across titles like Silver Surfer, Avengers, and Doctor Strange, Sorcerer Supreme. With three key issues to his name and a publishing history stretching all the way to 2026, Mephisto is no mere one-arc antagonist — he's a constant, creeping force woven into the very fabric of the Marvel cosmos. If you want to understand the darker corners of Marvel storytelling, following Mephisto's trail is as essential as it gets.