Warning! SPOILERS for Ms. Marvel.

Recently, the MCU Phase 4 has developed a theme that, while not entirely obvious, has created a continuity issue in the franchise. Marvel’s sweeping collection of movies has covered multiple topics and motifs since 2008, but Phase 4 has begun to tread new ground with new heroes. These storylines have broached topics that were never addressed in Phases 1-3 or have approached themes from a new perspective, which, while refreshing, comes with pitfalls.

Phase 4 titles have changed the MCU's future but also created a burgeoning continuity between Shang-Chi and the Legend of the Ten Rings, Eternals, and Ms. Marvel. While these stories seem disparate initially, as they each cover different heroes from different parts of the world, they do have more in common than meets the eye. All three stories share common themes of dealing with complicated family relationships, the loss of a family member, and how one’s ancestors affect their present. But more specifically, all three contain a binding element that hasn’t been shown in the cinematic universe until recently.

Related: Why MCU Phase 4 Is So Much Darker Than Phases 1-3

While family or loss could inform the direction of the MCU’s divisive Phase 4 storylines, the secret theme that’s now creating continuity issues is the introduction of immortal (or seemingly immortal) characters. In Shang-Chi and the Legend of the Ten Rings, Eternals, and Ms. Marvel, audiences are introduced to characters with preternatural lifespans, such as Shang-Chi’s father, Xu Wenwu, the entirety of the Eternals team, and the ClanDestines, respectively. There’s nothing wrong with creating long-lived characters, nor were any of these titles made individually worse for their inclusion. However, when presented together, they do cause issues for the greater MCU.

The MCU Introducing Immortals Is Creating Problems For Continuity

Tony Leung as Wenwu Mandarin in Shang Chi and Iman Vellani as Kamala Khan in Ms Marvel

With the introduction of immortals, Phase 4 of the MCU added continuity issues to an already-complex universe due to these characters’ overlapping timelines. For example, in Eternals, the last Deviants were killed around 1521. Meanwhile, Wenwu found the Ten Rings 1,000 years ago from the movie’s present day, meaning that he became immortal around 1021. While it's unknown how old Wenwu is in Shang-Chi, this gave Wenwu 500 years to notice the presence of both the Deviants and the Eternals. Mutually, the Eternals, even while fractured, had to have heard of Wenwu’s conquests and his legendary immortal status. Furthermore, in the mid-1900s, the ClanDestines steal the bangle they need to get back to the Noor Dimension from an abandoned Ten Rings ruin. While Ms. Marvel doesn’t state how long the ClanDestines been exiled on Earth, if it was long enough to hunt down the secrets of the Ten Rings, they had to have been present on the planet for a long time. It would certainly have been long enough that Wenwu should have been aware that someone was hunting for Marvel's infamous Ten Rings. Either way, it's hard to believe that these three immortal sects were not aware of each other.

It is true that in each of these stories, MCU Phase 4 does provide reasons for the immortals to avoid each other. The Eternals were ordered not to interfere in human affairs and Wenwu had no reason to engage with others like himself while running the Ten Rings from the shadows. Equally, the ClanDestines' only goal was to return home, and their seeming dislike for humanity encouraged no fraternization with Earth’s inhabitants. With each group strongly entrenched in their extended goals, there’s little cause for them to interact.

But while the secret, immortal theme of the MCU’s Phase 4 is technically plausible without any convolution, it does add another layer of complication to its stories going forward. With theories abounding that Ms. Marvel introduced the X-Men to the MCU, including another immortal hero, Wolverine, it will only be more difficult to keep these characters apart. In a franchise billing itself on the singular interconnectedness of its universe, continuity is critical, making it interesting to see how MCU Phase 4 will handle these increasingly long character threads.

Next: Phase 4 Is Already Teasing A New War Is Coming To The MCU 

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