The Marvel Cinematic Universe has countless moments where the fate of the world is decided by a single choice or event. Marvel's What If...? illustrates that very clearly from its first episode. But even in What If...?, some events and changes stand out as particularly shocking. Most notably, in What If... Ultron Won?, the rogue AI manages to transfer his consciousness into Vision's body.
Using his new vessel, Ultron takes over the world and even defeats Thanos, claiming the Infinity Stones for himself. The end result is a villain who is almost unfairly powerful, even by MCU standards. In fact, Infinity Ultron may have very well broken MCU's power scaling, challenging the audience's perspective on the true strength of the characters they know and love.
10 Earth's Mightiest Heroes Are No Match For Him
The Avengers may have defeated Ultron originally, but in Vision's body, they're no match for him. In MCU canon, JARVIS is able to keep the nuclear codes from the rogue AI. This version of Ultron doesn't let JARVIS stop him. Despite the Avengers' best efforts, Ultron obtains all the nuclear code and triggers an apocalyptic nuclear event on Earth. The only people shown alive in the aftermath are Black Widow and Hawkeye.
9 Wanda Maximoff Is Removed Before She Can Become A Problem
Interestingly enough, it's unclear what happened to Wanda Maximoff before the nuclear bombing. In the original story, she was instrumental in Ultron's creation, as it was her mind manipulation that led to Tony Stark experimenting on the scepter. She and her brother Pietro turned on Ultron after she detected Ultron's true purpose during the transfer of his consciousness. As a result, Wanda undid the brainwashing on Helen Cho, which caused the scientist to pause the upload of Ultron's mind. This gave the Avengers enough time to intervene and retrieve the Cradle.
She's never actually shown in What If...? but she must have had the same role in Ultron's creation. However, it is possible that in this alternate universe, Wanda doesn't notice Ultron's plan. At this point in time, Wanda hasn't yet reached her full potential as the Scarlet Witch. As such, Ultron must have removed her before she became a problem, maybe even before he became Infinity Ultron. That already eliminates one of the most powerful characters in the MCU.
8 Ultron One-Shots Thanos Before He Even Claims The Infinity Stones
Ultron accomplishes his goal of spreading his twisted form of peace, leaving Earth a barren wasteland of death and destruction. As Ultron surveys the results of his labors, Thanos shows up. He is in possession of the Gauntlet, now lacking only the Mind Stone to complete it. Ultron takes one look at him and splits him in two using a laser beam coming from the Mind Stone.
This is very problematic, as it blows the previously established power ranking of the MCU to smithereens. Even without the Gauntlet, Thanos has always been a formidable opponent. The only Avenger capable of even drawing his blood on Titan was Iron Man, and that took everything Tony had at his disposal. Wanda Maximoff seemed capable of defeating Thanos in Endgame, but it wasn't exactly effortless on her part. For Ultron, it takes seconds. This suggests that Vision may have been the most powerful Avenger all along, which makes his poor performance in Infinity War even more absurd and frustrating.
7 Ultron's Destruction Of Countless Planets Shows Just How Dangerous He Truly Is
After he claims the Infinity Stones from Thanos, Ultron expands his mission of destruction to engulf the whole universe. He is shown unleashing havoc upon planets like Asgard, Ego, and Sakaar. The Living Planet can do nothing to stop him and Taneleer Tivan just watches in horror as Ultron and his sentries obliterate everything in their path. Even the Guardians of the Galaxy briefly show up, but they're just as powerless as the Avengers.
6 His Fight With Captain Marvel Is Almost Anticlimactic In Length
The last hope of the universe seems to be Captain Marvel, and she does hold her own far better than other heroes. They clash during Ultron's invasion of Xandar, and she attempts to destroy him by shoving him into the planet's core. It's a good effort, but it doesn't end well for Carol. Ultron blows up the planet using the Gauntlet, killing Captain Marvel in the process. Carol has survived extreme damage in the past, but Ultron is just too powerful.
5 Ultron Senses The Watcher's Gaze On Him
Ultron doesn't give up until he achieves his purpose, that of remaking the universe in his image and killing the life forms he sees as inferior and obsolete. After his task is done, he is left despondent, as he doesn't know what to do. That is when he senses the Watcher's gaze on him. A similar incident has happened in the past in What If...?, when Doctor Strange Supreme asked for the Watcher's aid to save his universe.
Based on the Watcher's reaction, though, Ultron shouldn't have been able to feel him. Doctor Strange's experience may have been understandable, as he was summoning monsters from alternate dimensions and must have therefore formed a connection with the Multiverse. Ultron didn't have that. The Watcher should have been beyond his reach – and yet, he isn't.
4 Infinity Ultron Cracks The Barriers Between Dimensions
Ultron's power goes beyond simply perceiving the Watcher. As soon as Uatu realizes Ultron has sensed him, he retreats into the Nexus of All Realities. But that doesn't help him, as Ultron cracks the barrier between dimensions. The amount of power necessary to do this is mind-boggling, as it challenges the rules of every reality in existence.
3 His Confrontation With The Watcher Twists The Fabric Of Dimensions
Ultron and The Watcher engage in battle and the conflict spills from the Nexus of All Realities into various universes. The power the two emanate cracks the boundaries between worlds, but in the end, the Watcher fails to defeat Ultron. As Ultron pins him down and hits him, reality itself shifts around them. Uatu is forced to flee, leaving the Multiverse at the mercy of Infinity Ultron.
As the two fight, Ultron comments that the Watcher's main weakness is his inability to act. This may be part of the reason why Uatu loses the battle to Ultron. Still, the fact remains that Infinity Ultron beat a being that is basically a god in the MCU. It's yet another show of his incredible power.
2 Ultron Travels To Alternate Universes To Restart His Mission Of Destruction
After defeating the Watcher, Ultron gains the ability to travel through the Multiverse. This brings viewers back to the moment they first met the character, during What If... Thor Were An Only Child? It's safe to say that Party Prince Thor doesn't have much of a chance against Infinity Ultron. One can only assume that, after completing his work in Party Thor's universe, Ultron intends to move on to other worlds.
It's very unusual for a character to have this kind of mobility. Other than the Watcher, the only being with this kind of access to the Multiverse would be Loki's He Who Remains, and his most probable identity is Kang the Conqueror. But Kang doesn't show up at all in What If...?, which may make some fans wonder if Infinity Ultron has simply defeated him off-screen, just as easily as he did with Ego and the Asgardians.
1 Infinity Ultron Forces The Watcher To Turn To Doctor Strange Supreme For Help
Following his defeat at the hands of Ultron, the Watcher retreats into the ruined universe of Doctor Strange Supreme. Desperate, Uatu breaks his vow of non-interference and asks for Doctor Strange's help.
Uatu has done similar things in the comics, but in What If...? he has so far stood by and impassively watched universes being destroyed. The fact that he finally abandons his way of life speaks volumes to just how much of a threat Ultron is.