Doctor Strange in the Multiverse of Madness set up Stephen Strange to be a key player in the Multiverse Saga. Speaking at San Diego Comic-Con 2022, Marvel Studios president Kevin Feige revealed that Phases 4-6 of the MCU are officially titled "The Multiverse Saga." Marvel is building up towards an epic confrontation with Kang the Conqueror in Avengers: The Kang Dynasty, but the climax will be a multiversal catastrophe in Avengers: Secret Wars.
Doctor Strange is clearly being positioned for a major role in the Multiverse Saga. He took what can best be described as a multiversal road trip in Doctor Strange 2, and he learned the greatest threat posed by interdimensional travel. Should a traveler from one dimension leave too great a "footprint" on another, they risk causing an event called an incursion in which multiple timelines are mutually destroyed. Strange returned to Earth-616 transformed by his experiences, and Doctor Strange in the Multiverse of Madness' post-credits scene saw him head out into the multiverse to try to prevent an incursion he had apparently caused.
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Avengers: Secret Wars is inspired by a multiversal comic book story by Jonathan Hickman and Esad Ribic. In the build-up to Secret Wars, Strange committed himself to saving the multiverse. He left Earth-616, traveling into the multiverse and joining a group called the Black Priests who were going to extreme lengths to prevent incursions running out of control. They had discovered all these incursions originated from alternate Earths, and began destroying Earths in order to save their native universes. Strange, viewing this as a radical form of surgery, became the greatest champion of the Black Priests — known
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