Marvel's What If...? Writer Explains A Presumed Infinity Stone Plot Hole

Last week, Marvel's "What If...?" animated series finally tilted its hand to reveal the endgame that's in store for the first season. Though the series was initially presented as an anthology series that kept each story contained within its own universe, fans had long expected that something would end up bringing the universes together. That something ended up being a terrifying version of Ultron that inhabits the body of Vision and wields all of the Infinity Stones. However, that powerful "new" villain had some Marvel Cinematic Universe fans scratching their heads and wondering if there was a plot hole left overlooked. In response, "What If...?" head writer A.C. Bradley has laid out the facts for concerned (or confused) fans.

In last week's episode of Marvel's "What If...?," the powerful new Ultron who defeated The Avengers obtained all of the Infinity Stones. After destroying a variety of realms in his own universe, the Infinity Stones suddenly made Ultron aware of The Watcher and all the other universes that the cosmic being was observing. This led to an epic comic book battle between Ultron and The Watcher where they were smashing through the alternate universes of the multiverse. 

It's that last detail that had fans questioning the powers Ultron was wielding with the Infinity Stones. Just earlier this year, "Loki" established that the Infinity Stones won't work if they're taken from one universe and into another. (The reason the Infinity Stones worked in "Avengers: Endgame" is because they traveled back in time to moments in their own universe to collect the Infinity Stones). So if Ultron and The Watcher are careening into different universes, how is the power of the Infinity Stones able to be harnessed within them? A.C. Bradley noticed the fan discourse about this subject online and took to Twitter to explain the situation:

Happy Monday! Just a reminder that Ultron is using the Infinity Stones to power himself (same universe being). Also he's legit punching across multiverses turning them into one messy universe soup. #Whatif #WhatifMarvel #WeDidOurHW #YouAreAllAmazing ♥️

— A.C. Bradley (@TheAshBradley) October 4, 2021

So there are basically two explanations here. First of all, Ultron isn't using the Infinity Stones to manipulate other universes. Instead, he's using the stones to give himself more power and abilities, so technically, as a being of his own universe, he's still using the power of the Infinity Stones within his own universe. But even if Ultron were using the Stones to manipulate other universes, it turns out that would be allowed too, because he's breaking the barriers between all these universes and creating a connection between them. 

It's that last detail that will lead us right into the first season finale for Marvel's "What If...?" animated series.

Marvel's "What If...?" will reveal what happens when the barriers between universes are broken. After last week's episode, we now know exactly how all of the alternate versions of Marvel's Avengers that we've seen throughout the show so far will come together. Captain Carter, T'Challa as Star-Lord, Erik Killmonger as Black Panther, Thor, Black Widow, and Gamora have all been seen assembling as a new team of Avengers, and they're presumably joining forces to take on the all-powerful Ultron.

However, what happens to all these universes once Ultron is defeated? Does everyone go back to their own universe? Or will they all stay together in this new expanded universe? We already know the next season of "What If...?" is in the works, so there are more stories to tell. But will they continue to be anthology episodes that come together for an epic finale, or will we merely follow each hero on their own adventures in their own alternate universes? We'll have to wait and see what Marvel's "What If...?" season finale has in store before we can start speculating properly.

The first season finale of Marvel's "What If...?" arrives on Disney+ on Wednesday, October 6.