The Marvel Cinematic Universe repeats Avengers: Endgame's Smart Hulk origin problem with Shang-Chi and the Legend of the Ten Rings. Hulk is one of the foundational pieces of the MCU, and his story has been relegated to supporting roles as a result of Universal owning his movie rights. This has meant Marvel Studios repeatedly using him in other characters' movies or as part of team-ups, like The Avengers. Still, Marvel managed to give Shang-Chi viewers a surprise at the end with a Mark Ruffalo cameo, and the true shock came with him in Bruce Banner's human form.

Hulk's MCU story has primarily been about him fighting to find the balance between being Bruce Banner and a giant green rage monster. However, Avengers: Endgame brought a massive change to Hulk's persona. Bruce spent time after Thanos' snap in a lab and emerged after successfully merging his brains with Hulk's brawn. Smart Hulk debuted early on in the movie, but Marvel Studios glossed over the actual transformation. Avengers: Endgame includes dialogue explaining the massive appearance change but never bothered showing it occur or provide specific details about this transformation. This was a big problem for many viewers, but some could find solace in the idea that Marvel will provide an answer later on.

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That's what makes Bruce's appearance in Shang-Chi's post-credits scene so unexpected and frustrating. This is his first appearance after Avengers: Endgame and the Smart Hulk form is already gone. Reversing the idea that Bruce will always be Smart Hulk isn't a total surprise, as it would mean Mark Ruffalo only appears through motion-capture work now. However, Shang-Chi is the second time Marvel has completely skipped over the explanation of a major development in Bruce/Hulk. To make matters even worse, Bruce's new look isn't even addressed in the Shang-Chi tag. The scene easily could've mentioned a reason why Bruce isn't Smart Hulk still, but it instead ignores a section of Hulk's arc that is worth exploring.

Marvel's troubles with figuring out what to do with Smart Hulk are quite clear. The MCU needed Bruce to become Smart Hulk so he could reverse Thanos' snap in Avengers: Endgame, but how he got to this point changed even after production on Avengers: Infinity War occurred. Deleted scenes confirm that Smart Hulk was originally supposed to emerge during the Battle of Wakanda. Bruce and Hulk merging into Smart Hulk happens fast there, and while it may have been one extra element Infinity War's ending didn't need, it was at least an on-screen origin for Smart Hulk. Marvel's decision to delay Smart Hulk's debut until Avengers: Endgame changed this plan and became the beginning of MCU speeding past key moments in Bruce's life.

It is unlikely that Shang-Chi was ever supposed to address Bruce's new look either. The cameo is meant to make fans ask questions about what happened to Smart Hulk and why Bruce reversed the transformation. This is one way Marvel can help build even more interest in She-Hulk, as the Disney+ show is now the odds-on-favorite to provide answers about Bruce undoing his Smart Hulk transformation. That doesn't make it any easier to accept Shang-Chi and the Legend of the Ten Rings failing to provide answers, though. Fans will now have to hope that the MCU doesn't make the same mistake a third time with She-Hulk either.

More: Does Smart Hulk's Shang-Chi Transformation Mean Abomination Can Change?

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