In the final moments of What If…? episode 7, the Watcher was given a massive surprise when an army of robots stepped into the universe, supposedly led by Vision after he obtained all six Infinity Stones. Although the shot of Vision’s face is pretty dark, the mind stone in his head makes it very clear who is causing a ripple in the Watcher’s plans for the What If…? timeline. However, a Reddit user proposed the theory that it isn’t really Vision at all.

Marvel fans who have seen Avengers: Age of Ultron know that Vision’s vibranium body was meant to be a vessel that carried Ultron’s consciousness inside of it. However, the power of the Mind Stone gave birth to a new AI altogether, which is how Vision came to be.

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Based on the fact that Vision was originally meant to be Ultron, it’s not unreasonable to believe that Ultron was successful in taking over the body before Vision had time to become his own person. The What If…? series takes place in a branch of the multiverse that is separate from the sacred timeline the MCU has been covering for the last 13 years. The Reddit fan theory suggests that in the What If…? timeline, Ultron gathered the Infinity Stones, therefore making him Infinity Ultron.

If it’s actually Infinity Ultron who appears in the show, and not Vision, that would also explain why he was acting so out of character in episode 5. The WandaVision parallels in episode 5 are painstakingly clear, as Wanda has become a zombie and Vision is feeding her parts of T’Challa after kidnapping him in San Francisco. The Vision fans have come to know in live-action MCU projects would have never done something so cruel. He was also the one who encouraged Wanda to let go of the past and move on from him after his death in WandaVision, making the episode 5 storyline quite a shock to many viewers.

If that were actually Infinity Ultron in episode 5, however, the total 180 from WandaVision would make a lot more sense. Ultron’s moral code is nowhere near as noble as Vision’s, so he’s far more willing to do something as heinous as kidnapping the king of Wakanda to feed his undead girlfriend.

The Watcher was fully aware of the evil Vision was doing in episode 5, but he was shocked to see the robot infestation that began unfolding at the end of episode 7. Nobody was prepared for Infinity Ultron to make an appearance, so posing as Vision could have been the reason why he managed to escape the gaze of the Watcher.

The Reddit theory presents a different idea, saying that perhaps it was something else which allowed for Infinity Ultron to go unnoticed by the Watcher. Ultron and the robot army (who look extremely similar to the ones from Avengers: Age of Ultron) traveled through a glowing light, which appears to be a portal. The Reddit user speculates that the portal is what blocked the Watcher’s gaze from Infinity Ultron, and that he’s been using it to travel throughout the multiverse.

As far as the Watcher knows, Infinity Ultron wasn’t supposed to be created. If Ultron were to have an interdimensional portal that allowed him to hide in the places the Watcher can’t see, however, that would explain why his appearance came as such a shock.

Assuming Infinity Ultron is the big bad all of the characters will be facing in the final episodes of the series, the heroes have an intense journey ahead of them. To become Infinity Ultron, he had to acquire Vision’s vibranium body and defeat Thanos, all while operating in secret so that he wasn’t made by the Watcher.

It took the Avengers years to finally defeat Thanos during the Infinity Saga once he had acquired all six stones. Beating Infinity Ultron will likely be twice as hard, since he’s virtually indestructible, on top of harnessing the greatest power in the universe. The Reddit user believes that the Watcher will start to take a more hands-on approach in the remaining What If…? episodes, whether that be investigating how Infinity Ultron managed to sneak past him, or engaging in the actual fight.

The Watcher’s participation might be the only chance the heroes have to defeat Infinity Ultron. Based on how Infinity Ultron managed to evade him for so long, it’ll still be a massive challenge for the new team of heroes to take Ultron down, even if the Watcher intervenes.

With only a few episodes left, it’ll no doubt be interesting to see how the heroes defeat Infinity Ultron at his maximum level of power. Accomplishing such a task might not even be possible in only two episodes. Whether or not that means there will be a second season is unclear, but there’s still a possibility that the heroes won’t defeat Ultron at all. Given how bleak some of the endings have been for previous episodes, there’s definitely a chance that things will take a tragic turn.

New episodes of What If…? are currently streaming every Wednesday on Disney Plus.

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