What is the name of the South Park superhero alter ego of Butters Stotch?

The South Park superhero alter ego of Butters Stotch is Professor Chaos. After Stan, Kyle, and Cartman replace Butters with Tweek as their fourth friend, the rejected Butters adopts a supervillain persona to get revenge.

Professor Chaos is Butters's deliberately theatrical attempt to become a dangerous comic-book villain. He wears a green cape, helmet, and gauntlets made from cardboard and aluminum foil, visually parodying Marvel's Doctor Doom. His grand plans usually collapse because Butters is naïve, poorly prepared, and far less threatening than he imagines.

The character receives major attention in the season-six episodes “Professor Chaos” and “The Simpsons Already Did It.” Butters also gives his sidekick, Dougie, the villain name General Disarray. Although “Human Kite” and “Toolshed” are South Park superhero identities, they belong to other characters in the show's superhero parody universe.

Professor Chaos later appears in South Park video games, including The Stick of Truth and The Fractured but Whole. In the future-set special The Return of Covid, Butters uses the related alias Victor Chaos while running an absurd investment scheme.