Scheduled for a spring 2023 release, Guardian's of the Galaxy vol. 3 may still be a painfully long way off for fans of the series, but what the group has grown into for the MCU in the hands of James Gunn and the Russo Brothers is something truly special already. In the meantime, fans have been speculating like crazy, even causing Gunn to have to debunk rumors surrounding the new movie.

While focusing on details that are still unknown might not be the best approach, there's already plenty of fascinating trivia surrounding the movies to get to know before the new one comes out. These are some of the coolest Guardians of the Galaxy facts.

Chris Pratt Didn't Expect To Play Star-Lord

Chris Pratt As Peter Quill In Guardians Of The Galaxy

During the casting of The Guardians of the Galaxy, James Gunn didn't have a clear idea of who he wanted to play Peter Quill in the movie. Although Pratt was suggested, he initially didn't look like a great fit for the movie, partly due to the amount of weight he'd put on for a role in the Vince Vaughn comedy Delivery Man.

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Pratt had already had some disappointing auditions for blockbuster roles but nevertheless, as he told HuffingtonPost, he thought that if he had the chance to lose weight he'd be perfect for Quill. As it turns out, he had already impressed Gunn during their initial meeting and his place in the movie was basically set in stone.

Groot Is Based On James Gunn's Dog

A poster featuring Groot in Guardians Of The Galaxy.

A big part of why Guardians of the Galaxy is the most rewatchable Phase 2 MCU movie is the charm of characters like Groot, who couldn't have appeared anywhere else. What's less known about the tree of few words is that James Gunn based his interpretation of the character on his own dog.

In order to perform the role of Groot, Vin Diesel was forced to say the line "I am Groot" an absurd amount of times in countless different ways, making it a role unlike any other. It's no surprise that the actor found a role with such a limited vocabulary uniquely challenging, as reported by The Independent.

Playing Drax and Gamora Required Intense Make-Up Routines

Gamora standing in the line-up in Guardians of the Galaxy

Although a good helping of CGI was used to ensure that characters like Gamora and Drax look as amazing as they do in the Guardians of the Galaxy movies, the make-up routine that Dave Bautista and Zoe Saldaña still had to undergo every day on set was an uncomfortable process that took hours.

For the first movie, this meant the actors sitting in place for several hours while it was applied but, as reported in Metro, the make-up team was able to shave off a huge chunk of that for the second movie, to the relief of both. Their use of real make-up rather than relying too much on CGI paid off, even resulting in an Academy Award nomination in the Make-up category for the first movie.

James Gunn Hung Out With Real Racoons To Get A Feel For Rocket

Baby Groot on Rocket Racoon's shoulder in Guardians of the Galaxy Movie

Although Rocket is a very human character in some ways, albeit an extremely dangerous one, James Gunn looked to the animals the character is based on for inspiration. In the lead-up to the first movie, the director studied raccoons and even had some bought in so he could see their personalities in real life.

It's no surprise then that Rocket is such a ragged, animalistic character in the movies. One odd thing about this is that, whereas the comic book version of Rocket is simply an anthropomorphic raccoon, the movie version is a genetically engineered being with no knowledge of what a raccoon even is, a detail people often mistake for comics canon.

Guardians Of The Galaxy Was The First Movie To Feature Josh Brolin's Thanos

Guardians of the Galaxy Thanos Close Up

First revealed to be the being behind Loki's effort to obtain the tesseract in the first Avengers movie, Thanos was originally portrayed in the MCU by Damion Poitier. However, to suit his larger role in the upcoming next phase of the MCU, the character was recast, with Josh Brolin taking over for the first time in Guardians of the Galaxy Vol.1.

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This actually caused some difficulty for James Gunn, who struggled to fit this important character for the MCU into the first movie. Gunn told Vulture that he still wasn't sure if the character's appearance worked well in the lead-up to its release, as it was a moment designed entirely to progress the MCU and not the movie itself.

The Soundtrack Achieved A Billboard Record

Cover of Awesome Mix Volume 1 from Guardians of the Galaxy

With incredible hits from the 70s like Bowie's "Moonage Daydream" and Marvin Gaye and Tammi Terrel's "Ain't No Mountain High Enough", Guardians of the Galaxy: Awesome Mix Vol.1 made for an incredible movie soundtrack album. Containing some of the best songs used in the MCU, it didn't need any original songs to become a hit all on its own.

This proved to be the case as the album did something completely unprecedented, becoming the first-ever soundtrack album to hit no.1 on the Billboard 200 without containing any new songs.

Chris Pratt Stole His Star-Lord Costume

Star-Lord in GOTG 2

Although Quill's mixtape has to be the most iconic prop from the Guardians of the Galaxy series, Chris Pratt arguably managed to sneak home an even better prize in the form of Star-Lord's outfit. It's far from the first time an actor has taken something from a set they weren't supposed to but an entire costume was ambitious.

His reasons for making off with the costume became clear though as Giant Freakin Robot reported that he's been using the costume to visit sick children and give them the chance to meet an armored-up superhero in person.

The Movie's Success Saved Legendary Marvel Writer Bill Mantlo

Rocket Raccon standing in Guardians of the galaxy

Bill Mantlo, the legendary Marvel Comics writer famous partly for co-creating Rocket Raccoon, tragically ended up in institutional care after a hit-and-run accident in the 90s left him severely injured. One of the surprise upsides of adapting the Guardians of the Galaxy comics and its massive success is the benefit they brought to the former writer.

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As his brother and guardian Mike Mantlo told The Hollywood Reporter, Bill was happily able to be moved out of the nursing home he'd stayed in for 20 years and into a new house where he could receive in-home care thanks to the compensation packages sent their way as a result of the movie adaptation.

James Gunn Conceived Of Ego's Arc Before Acquiring Rights To The Character

Ego talking to the Guardians of the Galaxy.

As a character related to the Fantastic 4, which 20th Century Fox retains the movie rights to, Ego the Living Planet was not a character the MCU had the rights to use when production of the second Guardians of the Galaxy began. However, Gunn's determination to have Ego be the father of Peter Quill paid off in the end.

Gunn told Empire that the casting of Ego was actually all thanks to Chris Pratt, who suggested Kurt Russell for the role. This turned out to be perfect as not only did the Escape From New York actor do an amazing job, but he also has the same kind of twinkling charm as Peter Quill making their connection seem believable.

Vin Diesel Has Voiced Groot in 16 Different Languages

Baby Groot waving

For Guardians of the Galaxy Vol.1, Vin Diesel voiced Groot in 6 different languages so that he could continue to be the voice of the character in a variety of localizations. This fact became well-known after a clip of the actor saying "I am Groot" in different languages went viral online.

Something that's less well-known is that Gunn had Vin Diesel step it up another notch for Guardians of the Galaxy Vol.2 and voice Groot in well over twice the amount of languages as he did for the first movie. To voice a character who can only say 3 words requires versatility, but doing it in 16 languages is on another level.

NEXT: The 10 Funniest Quotes In The Guardians Of The Galaxy Movies