At this year's San Diego Comic-Con, Guardians of the Galaxy Vol. 3 director James Gunn confirmed that Cosmo is part of the team in the threequel, revealing that Maria Bakalova will voice the character.
Interestingly, this isn't the first time that the MCU included Cosmo. In the first Guardians of the Galaxy movie, the space dog was kept as one of the Collector's specimens in his museum in Knowhere, with the character appearing alongside Howard the Duck in its post-credits scene.
Back then, fans still didn't know Cosmo's gender since she has a non-speaking role. And now, Gunn has finally revealed it during the Holiday Special.
James Gunn Confirms Gender-Swapping of MCU's Cosmo
Warning - the rest of this article contains spoilers for The Guardians of the Galaxy Holiday Special.
Maria Bakalova made her MCU debut as the voice of Cosmo in the Guardians of the Galaxy Holiday Special, thus confirming that Marvel Studios has gender-swapped the character who is originally a male in Marvel Comics.
In Marvel Comics, Cosmo was a test animal for the Soviet Space Program. He was later launched into Earth's orbit, but his spacecraft drifted out of orbit which sent him to Knowhere. His telekinetic powers came from cosmic rays that mutated him during his cosmic drift.
Square Enix's Guardians of the Galaxy game also depicted Cosmo as a male, with him serving as the Chief of Security at Knowhere.
When a fan pointed out that Cosmo was supposed to be a male, Holiday Special director James Gunn explained gender-swapping the character, saying that he's simply "going back to the original source material:"
"Cosmo is based on Laika, a female Soviet space dog who died in orbit in 1957 - I’m just going back to the original source material."
Will Cosmo Play a Big Role in Guardians Vol. 3?
Cosmo isn't the first MCU hero to be gender-swapped in live-action. Marvel also did the same thing for other notable characters, such as The Ancient One (Doctor Strange), Mar-Vell (Captain Marvel), and Makkari (Eternals).
Given that the aforementioned characters turned out well in the franchise, it's easy to assume that Cosmo will do just fine with the gender swap.
In fact, the High Evolutionary's involvement in Guardians of the Galaxy Vol. 3 presents a grand opportunity for Cosmo to play a big role.
Although Cosmo is not part of the villain's experiments, the new Guardian could relate to the High Evolutionary's test subjects, meaning that Gunn could've given her a major arc in the threequel.
Giving Cosmo a significant role would benefit the upcoming film, as it allows the character to be fleshed out more, which could serve as a piece of good news for her bright MCU future after the events of Vol. 3.
The Guardians of the Galaxy Holiday Special is now streaming on Disney+.