Top 10 Marvel Superheroes Who Turned Into Villains

Not every Marvel hero stays on the side of justice forever. Over the years, some of the most iconic characters have crossed the line, embracing darker paths that shocked fans. From tragic falls to mind control and personal vendettas, these twists reveal just how thin the line between hero and villain can be. This countdown explores the top 10 Marvel superheroes who turned into villains, breaking down the stories, motivations, and lasting impacts of their transformations. Whether temporary or permanent, these heel turns changed the Marvel Universe in unforgettable ways.