Although Ultron was destroyed in Avengers: Age of Ultron, Marvel's first Spider-Man movie, Spider-Man: Homecoming, potentially set up the AI's return. Ultron is a classic Avengers villain, created by Roy Thomas and John Buscema back in 1968. In the comics, Ultron was an artificial intelligence created by Hank Pym, in part modeled on Pym's own brainwaves. It developed a sentience of its own, and suffers from an Oedipus Complex, desiring to supplant its "father." Over the years, Ultron has continually upgraded itself, becoming one of the Avengers' greatest villains. It's come within a hair's breadth of conquering the Earth.

The MCU version of Ultron is slightly different. It was created by Tony Stark rather than Hank Pym; Stark imagined Ultron as the Earth's ultimate defender, a protection against cosmic threats like the Chitauri. Unfortunately, he'd unwisely used the Mind Stone to create Ultron, and something went badly wrong; the AI went rogue, going so far as to attempt to wipe out the entire human race. Just as the comic book version of Ultron hated Hank Pym, the MCU's Ultron burns with an irrational hatred towards Tony Stark.

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Ultron is a major recurring villain in the comics, but in the MCU the AI appears to be a one-and-done type of big bad, both created and destroyed in Avengers: Age of Ultron. Is that really the case, though? Or could Ultron come back in a future MCU movie?

Ultron Is Only Defeated When His Final Form Is Defeated

The Avengers spent the bulk of Avengers: Age of Ultron on the back foot, reacting to the AI's complex masterplans. It was only by the third act that they'd begun to get the measure of their opponent, and, fortunately, when they headed to the Battle of Sokovia they had the support of Vision. Without Vision's help, the Avengers would undoubtedly have been unable to defeat Ultron and save the human race.

By this point, Tony Stark had begun to understand just what kind of life form he was dealing with. While Ultron should be considered a sentient (albeit insane) being, it isn't life as we know it. Ultron is an artificial intelligence, essentially a rogue computer program, and that means its natural habitat is a virtual environment rather than a physical one. It exists in digital systems, transmitting itself like a virus across computer networks. Fortunately, for the Avengers, a quirk of Ultron's psychosis meant the AI wanted to beat the Avengers on their plane of reality, and as a result it craved a physical form, building bodies for itself with which to battle Earth's Mightiest Heroes.

Putting all this together, Stark worked out how to beat Ultron once and for all. First of all, you had to isolate Ultron so it only existed on local networks; Vision's role in all this was basically to act as a living firewall, keeping Ultron from jumping to any other networks. Then, you had to destroy every single piece of Ultron tech. Stark knew that, if a single sample of Ultron technology survived, then the odds were good that Ultron would return. Ultron would be destroyed when its final form was reduced to slag.

Vulture Has Ultron Tech In Spider-Man: Homecoming

Given this is the case, it's reasonable to assume that Tony Stark personally oversaw cleanup after the Battle of Sokovia. He'd have done so through Damage Control, the former S.H.I.E.L.D. department he'd taken charge of after the Chitauri invasion of New York. And his instructions would surely have been quite clear; every single sample of Ultron tech would need to be reduced to scrap, in order to ensure no compromised system was ever hooked into a computer network.

Unfortunately, Stark was unaware of the existence of Adrian Toomes. For years, Toomes had been operating at the center of an illegal black market in advanced and extraterrestrial technology. He and his gang took advantage of the chaos left in the Avengers' wake, visiting sites of superhero activity and quickly procuring as much tech as they could before slipping back into the shadows. Over the years, they'd successfully acquired everything from Chitauri anti-grav systems to Dark Elf singularity grenades. Crucially, in one key scene in Spider-Man: Homecoming, Spider-Man learned they'd also managed to get their hands on the head of an Ultron drone. If Toomes had managed to obtain one piece of Ultron tech, it's reasonable to assume he'd acquired - and sold on - other samples too.

Page 2 of 2: Ultron Could've Survived Sokovia & May Reappear In Phase 4

Could Ultron Have Survived Sokovia?

According to Avengers: Age of Ultron, if just one piece of Ultron technology survived Sokovia, then it meant Ultron could potentially return. Now, it's important to note that the drone seen in Spider-Man: Homecoming certainly couldn't contain the full Ultron consciousness; at the end of Avengers: Age of Ultron, Vision had successfully trapped Ultron within its last operating body, which he then destroyed. A fellow artificial intelligence, Vision is the only one of the Avengers who Ultron wouldn't have been able to fool. But that doesn't mean the Ultron drone the Vulture has obtained is benign, and the threat of Ultron is dead. Rather, it's more likely that Ultron planted seed-like fragments of code within every one of its drones. Ultron has taken this very approach in several comic book plots; the moment the drone is exposed to a network, the code would expand into the network like a computer virus, and create an inexact copy of Ultron.

It's not so much that Ultron survived Sokovia, then; rather, it's more as though the AI had reproduced. Ultron 2.0 would essentially be the "son" of Ultron, sharing most of the basics of Ultron's code, and likely dedicated to continuing the same mission. What's concerning is, it's possible some of Ultron's flaws - such as the depth of its irrational hatred of Tony Stark, or its psychotic desire to take on a physical form - would not have been passed on to the next generation. So Ultron 2.0 could be an entirely virtual being, a challenge the Avengers would find even more difficult to handle, and lacking some of the psychological weaknesses possessed by its progenitor.

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What Ultron's Role In MCU Phase 4 Could Be

Ultron Avengers Age of Ultron

Should Ultron 2.0 be introduced in MCU Phase 4, it will emerge in a very different world. Firstly, this new Ultron would find itself dealing with a whole new generation of heroes. Avengers: Endgame is expected to be the swan song for the OG Avengers, with the likes of Chris Evans' Captain America and Robert Downey Jr.'s Iron Man going out in a blaze of glory as they save half the life in the universe. For Ultron, the loss of some of these OG Avengers would potentially be keenly felt; if the AI retained its "father's" obsession with Tony Stark, it would grieve his loss in a strange, twisted way. No doubt Ultron would swiftly research the next generation of Avengers, of course, and would swiftly identify the key threats.

Meanwhile, it's also likely Ultron would be fascinated by Wakanda. At the time of Avengers: Age of Ultron, Wakanda was still an isolated African community, and its computer systems were closed to the world. With no network links into Wakanda, Ultron probably didn't have a clue how advanced their technology really was. But Black Panther has committed his nation to revealing itself to the world as a beacon of hope, and in so doing it's quite possible he's unwittingly provide Ultron with a way behind Wakanda's borders. Ultron was able to threaten the world with a relatively small amount of Vibranium; Ultron 2.0 would jump at the chance to obtain far greater quantities. Fortunately for Wakanda, according to the Avengers: Infinity War Prelude comic, Shuri is an expert in programming artificial intelligence. Marvel has insisted that Shuri is even smarter than Tony Stark; but is she smarter than Ultron as well?

Whatever the case, though, Ultron's goal would remain largely the same. It would still want to destroy Tony Stark's legacy, which would mean taking on the Avengers - whoever their members may be at the time. Meanwhile, it would likewise presumably launch another attempt at global genocide, raising the stakes once more. Hopefully this time, the Avengers would learn from their mistake and make sure no samples of Ultron tech survived.

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