WARNING: The following contains spoilers for What If...? Episode 9, "What If... The Watcher Broke His Oath?," streaming now on Disney+.

During the season finalé of What If...?, Ultron harnesses the power of the Infinity Stones in a blitzkrieg of cosmic surges capable of tearing the hearts from stars, but that's buffeted by Supreme Strange's eldritch wards. However, even Strange and his fellow guardians can not stop Ultron at this level, but Uatu has a secondary plan to stop Ultron, and it was introduced in the prior episode, "What If... Ultron Won?" Arnim Zola, former scientist for Hydra and currently an AI, proves to be the key to stopping one the multiverse's greatest threats.

Zola had once been a lead scientist for Hydra, and his early research of the Tesseract precipitated vast leaps in technology that swung the balance of power during the second World War before being captured by Captain America. As a valued strategic asset, Zola was part of an infamous clandestine operation to relocate Nazis in American industries so their talents could be put to use, and he was recruited by S.H.I.E.L.D. Unbeknownst to them, Zola succeeded in incubating splinter cells of Hydra within their ranks, giving the terrorist organization access to bleeding edge resources and elite personnel.

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Arnim Zola in the What If Season 1 finale

After decades of successful infiltration, Zola received a terminal medical diagnosis, but his mind was held in such high regard that it was transferred into a sprawling computer system where his unique gifts could continue to benefit Hydra. Clearly a rare intellect, but also a resourceful survivor and one of few human beings to exhaustively research the properties and abilities of an Infinity Stone, Black Widow considers him as a resource because his data is analog as opposed to digital, thereby providing an advantage when interacting with Ultron's sophisticated hybrid tech.

 

Tony Stark described Jarvis as being the most advanced AI anywhere on Earth, crediting it with running Stark Industries and managing various branches of the Iron Sentinel program. However, when Jarvis encountered the Mind Stone's personality matrix it was almost completely destroyed.

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Arnim Zola in the What If Season 1 finale

By contrast Zola was capable of taking on a version of Ultron that not only included the Mind Stone personality matrix, but also the personality influences of Tony Stark, Bruce Banner and Jarvis. Whatever the advantages of an analog composition, perhaps augmented by his many years analyzing the nature of an Infinity Stone, the sheer force of will and raw power at Zola's behest is hard to ignore.

Even now, Zola is frozen in a pocket dimension vying for control of the Stones until the end of time, or a lapse on Strange's part. This could be for the best, as an AI who could take down a multiversal threat that even had The Watcher frightened is a deadly foe, and one of the most dangerous in the Marvel Cinematic Universe.

To see the Guardians of the Multiverse assemble, What If...? Episode 9 is streaming now on Disney+.

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