After episode 8 saw an Infinity Stone-powered Ultron (Ross Marquand) breaking through the boundaries of the multiverse, What If...? episode 9, “What If… The Watcher Broke His Oath?,” has The Watcher team up with Doctor Strange to bring together a team capable of beating Ultron. Along with Strange he gathers heroes from five other timelines. Captain Carter, Party Thor, T’Challa/Star-Lord, and Erik Killmonger all come from previous episodes. Gamora is also introduced, appearing from a universe that has not been previously shown.

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The Watcher, Uatu (Jeffrey Wright), has been watching the multiverse and the success of his plan shows that he picked the right team. Each member of the Guardians of the Multiverse has an important part to play in the final battle, and the reasons behind those choices shows the true power of The Watcher.

Doctor Strange/Strange Supreme

The selection of the "evil" Doctor Strange (Benedict Cumberbatch) from the timeline where he destroys his universe is perhaps the most well established. At the end of What If...? episode 8, The Watcher its that he needs Strange’s help to save the multiverse. Strange makes perfect sense as a team leader for the new group as he appears to be the most powerful single being that is show of What If…? outside of potentially The Watcher and the upgraded Ultron. Additionally, after realizing what he has done at the end of his episode, Strange was filled with remorse and eager for a chance at redemption. Defeating Ultron would fulfil that exact need and he is already aware of the multiverse and The Watcher so he is the natural first call for The Watcher.

Party Thor

Party Thor (Chris Hemsworth) might seem like an odd choice for The Watcher to have made, especially from a universe that has been shown to include a fully powered Captain Marvel. However, episode 8 had already shown Captain Marvel being defeated by Ultron, so reintroducing her here might have felt repetitive. While the Thor of the main MCU timeline has become (relatively) more cautious and reserved, Party Thor brings an important element to the Guardians of the Multiverse: he can draw Ultron’s attention and is extremely resilient. His loud and excessive nature make him the perfect distraction to allow other team to enact The Watcher’s plan.

T’Challa/Star-Lord

T’Challa’s iteration of Star-Lord (Chadwick Boseman) was chosen for his ability to embody the eloquence and honor of Black Panther with the thievery and underhandedness of Peter Quill. While Doctor Strange might be a good leader from a point of view of power, skill, and planning, he is not the best at inspirational speeches, and T’Challa is able to motivate the team more effectively. He’s key to The Watcher’s plan for his ability to use his “sticky fingers” to steal the Soul Stone from Ultron without him noticing, a true testament to Yondu’s parenting.

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Gamora

Gamora’s (Cynthia McWilliams) appearance in the What If…? season 1 finale might seem to come out of nowhere; this is because the original season was intended to include 10 episodes, but Gamora’s episode was bumped to season 2 due to COVID-19 related issues. Nevertheless, it is clear that this Gamora can play a pivotal role in The Watcher’s plan. In her own timeline she has been instrumental in defeating Thanos (claiming his weapon and armor) and has destroyed the Infinity Stones with the Infinity Crusher. While this part of the plan might have been a ruse to keep the Guardians of the Multiverse fighting until Strange was able to close Ultron in his own dimension, her presence and knowledge of how to destroy Infinity Stones was crucial for The Watcher’s plan.

Erik Killmonger

At first glance, Killmonger and Arnim Zola to become trapped in an eternal struggle for the stones.

Natasha Romanoff/Black Widow

For the Guardians of the Multiverse themselves, Natasha Romanoff’s (Lake Bell) appearance seems to happen by chance. However, The Watcher knew that she would become involved and be an important part of stopping Ultron. When The Watcher creates a portal for them to escape from Ultron through with the Soul Stone, he could have taken them anywhere in the multiverse, but took them to Natasha’s universe and to the one place there was still a living being. His selection of her was as deliberate as any of the others, and he relied on her as being the one person in existence with access to an arrow loaded with the Zola virus and with nothing to lose allowing her to risk her life in the final battle.

Captain Carter

Captain Carter (Haley Atwell) was the original team member shown in What If…?; however, the reason for her selection for the Guardians of the Multiverse is tied to how she is set up in the final episode of What If…? season 1. While she is a powerful super-soldier driven by honor, the same could have been said of any iteration of Captain America and The Watcher could have taken the Steve Rogers from the episode 3 universe. However, Captain Carter has developed a close relationship with Natasha Romanoff and is one of very few people that she would trust or allow to call her a BFF. Captain Carter was necessary for The Watcher’s plan for her ability to put Natasha at ease and to work in unison with her in the fight against Ultron.

Next: Every MCU Easter Egg In What If? Episode 9