Warning: Contains spoilers for Marvel’s What If…? episode 8.

A moment in Marvel's What If…? just revealed the biggest problem that Marvel faces with the multiverse. The use of multiple continuities and timelines is a staple part of comic storytelling and plays a large part in both Marvel Comics and DC. However, a storyline that sees them collapse in on themselves and offers potentially limitless opportunities to cross narrative boundaries could easily push the MCU beyond its own limits of credibility.

In What If…? episode 8, “What If… Ultron Won?,” he claims the Infinity Stones and uses them to destroy life throughout the universe. He then becomes aware of The Watcher, Uatu (Jeffrey Wright), and seeks to breaks through the boundary of the multiverses to confront him. When The Watcher exclaims that this shouldn’t be possible, Ultron responds by saying “Oh, but anything is possible in a multiverse.”

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Ultron’s What If…? comment about the multiverse explains both the wonderful potential for the MCU’s multiverse but also the treacherous position Marvel has put itself in by introducing it. With virtually anything being possible in the multiverse, where boundaries can so easily be crossed, it could be very tempting for the MCU to literally do anything, no matter how ridiculous. This has already been seen at its limit in the trailer for Spider-Man: No Way Home, a trailer that engages in some extreme fan service by bringing back past iterations of Spider-Man villains. If left unchecked, the multiverse could lead way to nonsensical storylines or unbelievable and unsatisfying conclusions that just rely on something unlikely coming from the multiverse. This also threatens to worsen the MCU’s already tenuous relationship with closure and permanent character deaths as it would always be possible to bring a character back to life, as with Gamora in Avengers: Endgame.

What If MCU Ultron Multiverse

They could avoid this problem by locking down the multiverse quickly. However, this would present a problem of its own as Marvel has spent so much time setting the concept up that to immediately close it down would leave the idea falling flat. It seems unlikely that they plan to go this route given that the multiverse promises to be a huge part of Phase 4. It has already been central to the plot of Loki and is the entire premise for What If…?. While both Spider-Man: No Way Home and Doctor Strange and the Multiverse of Madness are verified to deal with the effects of the multiverse, Kang has been set up as a longer-term multiverse villain that is announced to still be around during Ant-Man and the Wasp: Quantumania.

The multiverse risks being too big for the MCU to focus on coherently. Even as Marvel is looking to expand their storytelling and branching out to the Disney+ MCU TV shows if the multiverse becomes the problem and solution to every story they’re telling it will easily become overwhelming. With this, Ultron's claim about the endless possibility of the multiverse in What If...? should serve as a sort of warning for Marvel. Unless the MCU can find a way to limit the scope of the multiverse to be more manageable, it ultimately risks becoming an altogether grand superhero failure.

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Marvel’s What If…? releases new episodes Wednesdays on Disney+.

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