Shang-Chi Teases The Return Of Iron Man 3's Extremis

Shang-Chi and the Legend of the Ten Rings teases the return of Extremis-enhanced people from Iron Man 3. The 25th movie in the Marvel Cinematic Universe is a standalone origin story for Simu Liu's Master of Kung Fu. As the second film in Phase 4, Shang-Chi also plays a prominent role in setting up what the MCU's future will look like after Avengers: Endgame. The very end of the film is loaded with familiar faces, but the main story also sneaks in several references to the larger universe and the MCU's past.

While Marvel Studios sprinkled references throughout Shang-Chi, Xialing's underground fighting tournament is loaded with Easter eggs and MCU connections. The marquee example of this came with the return of a Doctor Strange sorcerer and The Incredible Hulk's villain, as the two squared off in the ring. The pairing of Wong (Benedict Wong) and Abomination (Tim Roth) was unexpected, but it showed that nothing was off-limits for this section of the film. It is also during this scene that one of the other Black Widows from Black Widow can be seen competing, and her opponent should also look familiar to MCU fans.

As Shang-Chi and Katy (Awkwafina) are guided through the Golden Daggers Club, they pass various small-level fights that Xialing has orchestrated. The Black Widow cameo happens quickly and is admittedly somewhat tough to see in the movie itself, but that could be because Marvel wanted to highlight her opponent more. The brief shot of this fight showed her shirtless male opponent have a red/orange glow shining through his skin. This look in the MCU is synonymous with people who have been injected with the Extremis serum developed by Maya Hansen and weaponized by Aldrich Killian in Iron Man 3. The reddish glow of their skin is typically a sign that Extremis is healing the body or that it is unstable, which results in the person blowing up. Considering this unidentified Extremis soldier is in a fight, it is safe to assume that the serum is healing the injuries he's sustaining.

Extremis Fighter in the Shang-Chi Fighting Tournament

The MCU movies have only used Extremis in Iron Man 3 prior to this Easter egg in Shang-Chi and the Legend of the Ten Rings. It is curious to see those enhanced with it at this point in the MCU timeline since Iron Man 3 didn't indicate that any of Killian's men survived. However, Agents of SHIELD did revive the Extremis project as part of the Centipede program, which combined it with gamma radiation and Chiaturi technology to try and create a new kind of MCU super soldier. Agents of SHIELD's place in the MCU is highly debatable, though, and this would be a surprising way for Marvel Studios to build on what the show did.

Now that Shang-Chi and the Legend of the Ten Rings has brought Extremis back to the MCU, it could be part of a larger plan from Marvel Studios. Since it was a product of AIM's research, the re-emergence of Extremis might signal that Killian's organization is back in some form. This could be done under new leadership from AIM, such as MODOK. There's also the chance that this could be a seed planted to enable Aldrich Killian to return. Guy Pearce is open to playing him again, so maybe he didn't die from the bomb Pepper Potts shot at him and he's rebuilding his army of Extremis soldiers.

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