Rumors about the future of the DCEU hint at how the ending of Andy Muschietti's The Flash will use the multiverse differently than Spider-Man: No Way Home. The concept of the multiverse has existed for several decades in the comics, but it has entered the world of Hollywood blockbusters only until very recently. Avengers: Endgame planted the first seeds with the Avengers' time-traveling mission, which paved the way for alternate timelines and modified realities in LokiWhat If...?, and Spider-Man: No Way Home.

Although the concept of the multiverse offers exciting prospects for every single one of Marvel and DC's characters, it doesn't actually have clear guidelines. Across the comics, movies, and the Arrowverse's Crisis on Infinite Earths, many alternate realities appear, get destroyed, and sometimes get rebuilt — some of them even merge with others, and others remain shrouded in mystery. So far, the MCU hasn't cleared up exactly how the multiverse works, but Doctor Strange in the Multiverse of Madness will probably make it easier to understand. As for the DCEU, The Flash is tasked with featuring the multiverse for the first time, and if rumors are true, Barry Allen's first standalone movie will also make its changes permanent.

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While Spider-Man: No Way Home's use of the MCU multiverse brought satisfying surprises for Marvel fans, it didn't make a considerable impact on anyone within the MCU besides Peter Parker. Even Doctor Strange, who performed the memory-wiping spell that brought Spider-Man's multiverse villains to Peter Parker's world, forgot about what happened in the movie. On the contrary, it's highly likely that Barry Allen's trip across alternate realities will bring definitive consequences to the DCEU. With Henry Cavill unlikely to return as Superman and Ben Affleck hanging the cape in The Flash (as well as the DCEU's departure from Zack Snyder's movies and Michael Keaton's promising future in Batgirl), fans can only expect to see a very different DCEU after the events of The Flash.

Ezra Miller's The Flash in the DCEU Multiverse

DC's iconic Flashpoint storyline, which offers the basis for the story of The Flash, is known for changing the entire DC landscape. In fact, Spider-Man: No Way Home briefly referenced the storyline with Flash Thompson's autobiography "Flashpoint: A Memoir - My Life as Peter Parker's Best Friend". Unlike Doctor Strange, Barry Allen doesn't have a library of tricks that can help him patch up the multiverse. Barry is usually depicted as a hero who uses the Speed Force to permanently change DC's multiverse when there are no other alternatives, and it's likely that The Flash will honor that quality.

Even if The Flash subverts expectations when it comes to how alternate realities work, it's more than evident that the DCEU needs permanent changes to move forward. The Flash offers the ideal explanation for why Michael Keaton's Batman accompanies Batgirl while The Batman exists in a separate reality, and it can replace Henry Cavill's Superman with Sasha Calle's Supergirl seamlessly afterward. Whatever surprises The Flash has in store, the DCEU will probably be very different by the time the credits roll.

More: Keaton's Batman Forever Exit Reason Makes His DCEU Return More Exciting

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