Despite often being regarded as the weakest of the Avengers series, Avengers: Age of Ultron has proven to be vital to the MCU's Multiverse Saga in many different ways. While awkwardly sitting as the middle installment of the Avengers films, Age of Ultron included many praise-worthy elements. From James Spader's fantastic turn as Ultron to the incredibly shot action and the banter between the titular team, Avengers: Age of Ultron contains a lot to love.

Similarly, many of the plot elements focused on in Age of Ultron massively helped set up the fantastic Phase 3. Tony and Steve's arguments, Thanos' post-credits scene, Tony's "retirement" from the Avengers, and Thor's Infinity Stone quest all ended up being vital to the MCU's Infinity Saga story. Beyond that though, Age of Ultron included a great deal of other elements, concepts, and characters that are proving to be important in the Marvel Cinematic Universe's present concerning Phases 4, 5, and beyond.

Related: 2 Age Of Ultron Scenes Prove It Had The Best Version Of The Avengers

9 Wanda Became The Scarlet Witch In HYDRA's Lab

The MCU's Phase 4 kicked off with WandaVision, a Disney+ show that established Wanda as the Scarlet Witch after years of the series denying the character her comic book name and visual style. While an important story for Phase 4, the basis of Wanda's Scarlet Witch origins were retroactively traced back to Avengers: Age of Ultron. In WandaVision, it was revealed that Wanda's first glimpse at her future as the Scarlet Witch came just before the second Avengers film when she was still a captive of HYDRA.

Admittedly, this was a retcon of Avengers: Age of Ultron which stated that the Mind Stone gave Wanda her powers as opposed to Phase 4's insistence that it simply empowered magic she already possessed. Regardless, it is clear that Wanda's backstory hinted at in Age of Ultron was vital for Phase 4's beginning. Not only was her time in HYDRA captivity mentioned, but her relationship with Pietro, her mother and father, and the bombing of Sokovia by STARK tech all played big parts in WandaVision's story, elements all set up in Avengers: Age of Ultron.

Related: No Avengers In MCU Phase 5 Avoids A Massive Age Of Ultron Problem

8 Vision’s Creation Could Link To Vision Quest

When concerning the other half of WandaVision, Avengers: Age of Ultron proved vital to Vision's Phase 4 story but also could tie into the character's future in Phase 6. Age of Ultron was the first project to include Vision, yet also began planting seeds for his and Wanda's future romance. This naturally came into play in WandaVision, with their relationship being the central focus of the show outside of the Scarlet Witch's origins.

In terms of Phase 6 though, the confirmed Vision Quest MCU show could include big Age of Ultron elements. With Vision Quest likely to center around White Vision coming to terms with his new memories after the finale of WandaVision, he could seek out his creator. That character is Helen Cho, who invented the Regeneration Cradle used to create Vision in Age of Ultron. If this is the case, another vital element of Avengers 2 that has been long forgotten could be crucial to a Phase 6 project.

7 Hulk's Age Of Ultron Ending Led To The Multiverse Saga's Skaar

Another element seeded in Avengers: Age of Ultron that both has been and could continue to be important in Phases 5 and 6 is Hulk's time on Sakaar. At the end of Ultron, Hulk flies away in a Quinjet, revealed to have landed on Sakaar in Thor: Ragnarok. In She-Hulk: Attorney at Law, Hulk was being tracked by ships from Sakaar, with Bruce traveling there to find out why. Hulk then returns to Earth with a son named Skaar, who was conceived during his two-year stint on the alien planet.

While Skaar only had a brief cameo in She-Hulk, it is hard to imagine Marvel Studios introducing the character if he was not going to be used in the future of the Multiverse Saga. With Skaar's MCU future all but confirmed, Avengers: Age of Ultron has yet again proved vital to a Phase 4-6 plot point. While it is unclear where Skaar will return to the MCU, Hulk siring a son due to his Ultron ending is a big connection between Phase 2 and Phase 4.

6 Falcon's New Avengers Introduction Led To Him Becoming Captain America

Undoubtedly one of the biggest plot points of Phase 4, and soon to be Phase 5, was Sam Wilson becoming Captain America. The Falcon and the Winter Soldier saw Sam coming to terms with Steve leaving him the Captain America shield, and eventually choosing to don the mantle going forward. This will continue in Phase 5's Captain America: New World Order, continuing Sam's journey as the titular hero.

While Falcon and the Winter Soldier was mainly responsible for portraying Sam's transition to Captain America, his inclusion in the New Avengers at the end of Age of Ultron set him on that path. Before Avengers 2, Sam was simply a sidekick of Captain America, with Ultron serving as a way to tie him into the Avengers for films like Captain America: Civil War, Avengers: Infinity War, and Avengers: Endgame. Without Avengers: Age of Ultron, Sam would have continued as a side character, meaning his transition to Captain America in Phases 4 and 5 would not have been possible.

5 Avengers 2 Introduced Hawkeye's Family For Phase 4

2021's Hawkeye saw the return of Clint Barton to Phase 4, with the story of the Disney+ series centering on Clint attempting to be home for Christmas with his family while mentoring Kate Bishop. Despite not playing huge roles in the show, Clint's family was a significant element in his emotional journey throughout the show, something that would not have been possible without Avengers: Age of Ultron. Ultron was the first film to divulge information about Clint's family, which proved important to his arc at the end of Phase 3 and the beginning of Phase 4.

4 Age Of Ultron Set Up The New Avengers Long Before The Multiverse Saga

With the confirmation of Avengers: The Kang Dynasty and Avengers: Secret Wars also came the confirmation of the New Avengers after the Infinity Saga's team was disbanded. With the Multiverse Saga setting up plenty of potential heroes for the team thus far, the concept of the New Avengers was seeded in Avengers: Age of Ultron. The end of that film flirted with the idea of the core Avengers retiring to be replaced with new heroes like Wanda, Vision, Falcon, and War Machine.

3 Vibranium's Bigger Focus In Ultron Could Foreshadow The MCU's Phase 5

While Vibranium was mentioned briefly in the Captain America series, Avengers: Age of Ultron introduced Ulysses Klaue and his Vibranium mining operation. These elements certainly played a big part in films like Black Panther and Black Panther: Wakanda Forever - due to the importance of Vibranium to the Wakandan people - but could also be vital foreshadowing for the rumors surrounding the MCU's Phase 5. These rumors center on Captain America: New World Order and Thunderbolts, theorizing that the films will connect through a Vibranium war led by the CIA's Val.

If this indeed turns out to be the story arc for two of Phase 5's biggest films, Age of Ultron can be credited as the first proper introduction of Vibranium to the MCU. Through Ulysses Klaue and Ultron, Vibranium became known as a vital MCU element rather than simply the basis of Captain America's shield. If Phase 5 then centers a story on the metal, Age of Ultron has yet another link to the Multiverse Saga.

2 Ulysses Klaue Foreshadowed She-Hulk's Intelligencia

Another Ulysses Klaue link to Phase 4 comes in the form of She-Hulk's Intelligencia. In She-Hulk, the group was introduced as an online platform dedicated to bringing down She-Hulk's character. While very different from their comic book counterpart, Intelligencia still played a big role in the show. In Age of Ultron, Klaue's file lists him as a former member of Intelligencia. While this was likely nothing more than an Easter egg in 2015, She-Hulk's introduction of the group means that Ultron foreshadowed their future appearance.

1 Scarlet Witch's Ultron Visions Link To Doctor Strange 2's Multiverse

Finally, another way Ultron links to the Multiverse Saga is through Doctor Strange in the Multiverse of Madness' exploration of the multiverse. In that film, it is established that dreams can function as windows into other universes. In Age of Ultron, Wanda forces all of the Avengers besides Hawkeye to suffer from visions and dreams of idyllic or tragic versions of their lives. This could retroactively be seen as insights into the multiverse through Wanda's magic. As the Scarlet Witch is apparently intrinsic to the multiverse, Avengers: Age of Ultron could have foreshadowed the events of Phase 4.