In Loki’s EP:1, Miss Minutes says that there was no control over the timeline at one point, causing a multitude of different realities. Those realities went to war with one another in a battle for supremacy, which ultimately caused the Time Keepers to step in and fix things. The different realities already went to war, the war already ended, and there is now one timeline. That’s the entire story of Secret Wars, and it has already happened in the MCU continuity.
Fans of the long-running series have their sights set on Secret Wars as the next on-screen event now that Avengers: Endgame is over and the Marvel Cinematic Universe is poised to explore the cosmos. For those unfamiliar, Secret Wars is a comicbooknarrative about several realities going to battle with one another, finally becoming a single narrative. This plot has a lot of promise in the MCU’s future, and Endgamefilmmakers Joe and Anthony Russo have already shown interest in adapting it.
This is undoubtedly a surprise for Marvel fans, but it doesn’t imply that there won’t be a Secret Wars tale later in the future that we really get to witness play out on-screen. After all, Secret Wars has already happened twice in the history of Marvel Comics.