The Guardians of the Galaxy Holiday Special features Bucky Barnes' vibranium arm in what is a perfect callback to one of the funniest jokes in Avengers: Infinity War. Upon seeing Bucky outfitted with a custom arm replacement from Wakanda in the third Avengers movie, Rocket memorably asks if he can buy the custom piece from the former Winter Soldier. Bucky quickly declines, and it seems unlikely that Rocket will ever actually end up with the iconic limb. However, it's made a reality in MCU's Phase 4.

In addition to proving again that the "Special Presentation" format works well for MCU properties following the success of Werewolf by Night, the Guardians Holiday Special answers questions about Knowhere and reveals that Mantis is Peter Quill's half-sister (sharing Ego as a father). Along with some subtle world-building, there is also an unsurprising amount of humor. Gunn's classic comedy style shines throughout the short feature, and the jokes serve a double purpose of being funny and also potentially affecting Rocket and Bucky in their next appearances.

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Rocket Getting Bucky's Arm Makes Infinity War Better (& Funnier)

Rocket asks Bucky for his arm in Avengers: Infinity War.

As a fun nod to Infinity War, Nebula gives Rocket the vibranium arm belonging to Bucky in The Guardians of the Galaxy Holiday Special. Infinity War is among the least comedic of all MCU movies, but the Guardians make jokes almost every time they meet another hero. In what was already a callback to Rocket asking for a prisoner's bionic eye in the original Guardians of the Galaxy, Rocket requesting a metal body part is arguably funnier the second time around. Seeing the joke pay off again in the Guardians Holiday Special is the latest way the MCU's Phase 4 retroactively improves Infinity War, making one of the few jokes even funnier upon rewatches.

The MCU often suffers from drawing a joke out too long, which means that funny moments are sometimes ruined by unneeded repetition. That being the case, re-introducing Bucky's arm as a quick gag risked retroactively ruining the funny line in Infinity War. However, the joke fits the tone of the Guardians Holiday Special. It's a perfect example of how jokes can work actively and retroactively in even the most serious and dour MCU movies.

What Rocket Getting Bucky's Arm Means For The MCU

Bucky in Falcon and Winter Soldier and Rocket with Bucky's arm in Guardians of the Galaxy Holiday Special

There's no clear answer as to what Rocket or Bucky will do now that the arm has changed hands, but writer and director James Gunn confirmed how Bucky's arm appears in the Guardians Holiday Special. Befitting Nebula's usual demeanor, Gunn revealed on Twitter that "...she couldn't help tearing off the arm because she was just feeling so freaking Christmasy!" With confirmation that the arm is the original piece and not a replica, Bucky will need a replacement before returning to action in Thunderbolts. Promo art shows Bucky with the same vibranium arm, so he'll either get a new version or somehow retrieve it from Rocket's possession.

While it's possible that the moment will be treated as a non-canon gag and Rocket won't be seen with it again, it's possible that the resident tech expert will be able to reverse-engineer something useful in one of the MCU's upcoming movies. He's known for tinkering, and material as powerful and with as much potential as vibranium could lead to even more impressive inventions and breakthroughs. With the heroes of the MCU once again heading towards a seemingly insurmountable challenge, both Bucky and Rocket will need to be at full strength to survive, and The Guardians of the Galaxy Holiday Special may play an essential role in that happening.

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