While it's generally believed that Vision killed Ultron in the final battle of Sokovia in the Avengers sequel, there is some potential evidence that Ultron survived beyond his first appearance in the MCU. Furthermore, the very existence of Vision is very much tied to Ultron himself, as he was meant to be Ultron's "vision" for a new mechanical world, devoid of humanity and its various flaws.

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When SWORD took Vision's body after his death in Infinity War, they claimed to Wanda that it was their responsibility to dismantle him, as Vision is one of the most sophisticated sentient weapons on the planet. However, they soon put him back together in the hopes of one day finding a power source to reboot him under their control. In the absence of the Mind Stone that was largely responsible for bringing Vision to life in the first place, it wasn't until they got their hands on Wanda's own residual power that they were able to bring Vision back online. However, this White Vision will most likely be different than the Vision Wanda once knew or recreated for her fantasy reality in Westview. Now, White Vision is ready to be deployed into Westview for the series finale, and he could be the perfect means for Ultron to get the body he's always wanted.

Vision Didn’t Kill Ultron In Avengers Sequel

In Age of Ultron's final battle, the Avengers managed to evacuate the entire Sokovian city that Ultron had lifted into the sky using vibranium and Chitauri technology, turning it into a massive meteor to wipe out mankind. They also shut down Ultron's connection to the internet, leaving his consciousness contained within the various drones he had constructed. Working together with the help of their new allies Wanda and Pietro Maximoff, the Avengers were able to break the city apart and destroy all of Ultron's drones, save for one.

This final drone holding Ultron's mind and core code was met by the Vision, the vibranium synthezoid powered by the Mind Stone meant for Ultron that Tony Stark and Bruce Banner co-opted by putting the A.I. JARVIS inside, creating a whole new being. Vision was integral in stopping Ultron's plans, though he did tell the Avengers before the battle that he was on "the side of life" when they questioned his allegiance. Keeping that in mind, it seems unlikely that Vision would have killed Ultron's final drone without somehow preserving Ultron's consciousness. After all, Vision's perception of life more than likely extended to the belief that Ultron was also alive, just as much as Vision is alive himself as a synthezoid. Likewise, the actual act of Vision destroying Ultron for good was not actually seen at the end of the film, as it was implied to have been done off-screen - the old "never found the body" trope.

Ultron Is a Part Of Vision

Regardless of whether or not Vision stored Ultron's consciousness after Age of Ultron, the wayward peacekeeping synthezoid is still a part of everything that makes up Vision's very mind and code. As confirmed by Bruce Banner in Infinity War, Vision's mind is "made up of a complex construct of overlays," and Banner goes on to reveal that elements of Tony, JARVIS, the Mind Stone, and Bruce himself are all interwoven and mixed together that also learn from one another, and Ultron is notably a part of these overlays as well.

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This was all in reference to the Avengers' debate about whether or not they could safely remove the Mind Stone from Vision's head and still keep him alive and intact afterward. While they attempted to do so, the heroes ran out of time when Thanos' forces invaded. Eventually, Thanos himself arrived at Earth, and he subsequently ripped the Mind Stone out of Vision's head, leaving the synthezoid grey and lifeless in Wanda's arms.

However, it's since been revealed that SWORD has dismantled and put Vision back together several different times after they recovered his body, and it's possible they didn't put him back the same way. Now that they've gained the power to finally revive Vision, it's possible that some of the worst elements of Vision's code have risen to take a stronger dominance in the absence of the Mind Stone, such as the portions belonging to Ultron.

What White Vision Being Ultron Means For WandaVision (& The MCU)

The finale of Marvel's WandaVision could very well begin with SWORD having no idea what they've just unleashed, inadvertently making an already volatile situation in Westview that much worse by adding Ultron into the mix with the body he always wanted, his original "vision." Whether it's the result of Vision having kept Ultron's core trapped within him since Age of Ultron that's now been freed, the Ultron parts of Vision's code taking over thanks to SWORD's tinkering, or even a mixture of the two, there's a least a logical pathway within the MCU's continuity for Ultron to make a return using White Vision.

While the WandaVision finale will no doubt see Wanda (officially named the Scarlet Witch) facing the fellow witch Agatha Harkness, the Vision created by Wanda will most likely be facing White Vision as the couple fights for their family and happy ending (before it inevitably falls apart). The White Vision in the comics lacked humanity and emotion, which it what the MCU version will presumedly be if SWORD ends up simply remote piloting him. However, it would certainly be much more dynamic if SWORD's control over White Vision was subverted by Ultron himself.

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While it seems as though Wanda's created Vision won't survive the end of Marvel's WandaVision, seeing an encore performance from the major MCU villain Ultron via White Vision would certainly up the intensity as the series comes to a close on Disney Plus, as Ultron has ties not just to Vision, but also to Wanda as well, as he was responsible for Avengers: Endgame.

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