The first Guardians of the Galaxy movie was a dazzling space adventure filled with bright colors and classic music that became a beloved movie in the Marvel Cinematic Universe. Director James Gunn, his crew and all of the actors involved in the sequel knew that going in, and they managed to deliver a movie that was exciting, unusual, spectacular and moving all at the same time. Now, Guardians of the Galaxy Vol. 2 has finally made it on home video, and with it comes an entertaining array of special features ranging from making-of documentary videos, to deleted scenes and a gag reel.

RELATED: 15 Marvel Movie Plots That Will Never Be Resolved

But if you're looking to get the best insight into the process of making the movie, the only source you can go to is the writer and director of the movie himself, James Gunn. Gunn was gracious enough to record a full audio commentary track to the film by his lonesome. Now, we understand that some of you might not want to devote two hours to watch/listen to this special feature. You'd rather just watch Guardians 2 for the 17th time. Well, CBR has you covered. Amid all the stories and anecdotes, we have cherry-picked 15 movie secrets we learned from James Gunn's commentary!

15 GROOT WAS SUPPOSED TO BE AN ADULT

Groot

After the first Guardians of the Galaxy movie, Groot became an extremely popular character, a standout in a group of standouts, a talking tree that became a toy and collectible sensation. The sequel left the character starting anew, and while it could have been entirely possible to have Groot become fully grown for Guardians Vol. 2, director James Gunn ultimately decided against it.

In fact, the director revealed in his commentary that when he first started working on Vol. 2, he intended to have Groot returned to his full size for the movie. However, he quickly felt that it was too repetitive a move, that he was retreading old ground instead of doing something new. And for that reason, we ultimately got the adorable Baby Groot as one of the stars of the film.

14 THAT AMAZING TRACKING SHOT SEQUENCE

baby groot dance gotg vol 2 header

Guardians of the Galaxy Vol. 2 looked to up the ante from its very first scene, and the movie managed to do just that with a tracking shot sequence that left all of us in the audience breathless. As the Guardians battle the Abilisk, the camera follows Baby Groot around as he proceeds to dance, dodge flying Guardians, tentacles and debris and chase around little alien rats.

The entire sequence is nothing short of phenomenal, mixing live-action and a dazzling array of colors and special effects. In the director's commentary, we learned that this very sequence was so complex that it went through 4,000 different versions. The sequence was produced all along the shoot of the movie, and it wasn't fully ready until a few weeks before the movie would be released.

13 PETER QUILL'S FAMOUS T-SHIRT

peter-quill-ego-talking

Even before Guardians Vol. 2 was released, people were wondering about Peter Quill's t-shirt, with its strange, stylized language. It was seen in the movie's trailers and posters, it was featured on toys and collectibles, and it was even sold as a shirt. Naturally, people grew curious as to the meaning of this shirt, not just by definition, but also by what it meant to Star-Lord, as a character.

The movie may have never given us answer, but James Gunn sure did – in his director's commentary. As it turns out, the t-shirt does indeed have a very special significance for Star-Lord. Written in a foreign alien language, the shirt says “Gear Shift,” which is the brand of one of Quill's favorite candy. Seeing as how there is candy everywhere in his spaceship, this shouldn't come as a surprise.

12 YONDU'S BIG FIN

When it comes to changing things from the source material, it turns out that some comic fans can be quite selective. In the first Guardians of the Galaxy, Yondu Udonta was re-invented as a space pirate with a small mohawk on his head, an echo of the big red fin he used to sport in the comics. But fans didn't seem to care about the changes brought to Yondu's entire character save for one thing: his fin.

In the director's commentary of Vol. 2, Gunn explained how the much bigger, much more comic book-accurate red fin that Yondu comes to wear in the movie was brought in to placate those fans, to give them something that they had been clamoring for. But rather than just make the change without reason or explanation, Gunn decided to use it as a part of Yondu's journey... and to make a bright (bloody) spectacle of it.

The first Guardians of the Galaxy movie began with an opening scene of a young Peter Quill losing his mother and being abducted by the Ravagers. That is when the opening Marvel logo kicked in, with its flipping pages and iconic music. Curiously, though, that wasn't the case for the sequel. Instead, the movie surprisingly started directly with the opening Marvel logo.

We came to learn that this was due to timing. As a matter of fact, as the Marvel Cinematic Universe keeps growing and expanding, so too does the opening Marvel logo changes and expands. The director's commentary informed us that the Marvel logo was supposed to appear after the opening scene with Ego and Meredith, but that it was moved to the beginning of the movie because it was now too long to be featured in-between two scenes.

10 MUSIC FOR THE CAST AND CREW

Guardians of the Galaxy Awesome Mix Vol. 1

With the soundtrack playing such an important role in the film, it's no wonder that the music was chosen well before cameras rolled. In fact, it wasn't just that the songs used in the film were selected ahead of time; part of the very original score by composer Tyler Bates was also recorded in advance. This was all done so that the actors, as well as the crew, could listen to the music as they filmed.

In the director's commentary, James Gunn explained that he wanted the actors and the camera operators to be able to act and move along to the beats of the music, so that they could feel the emotions and the vibes of the scenes just as the movie would intend. The score was mainly used in certain emotional and important scenes, like Yondu's emotional sacrifice to save Peter Quill.

9 YOUNG KURT RUSSELL

Young-Ego-Guardians-2

Guardians of the Galaxy Vol. 2 opened with a scene set in 1980 featuring Peter Quill's mother Meredith, and Ego, played by a very-young looking Kurt Russell. For this scene, the 66 year-old actor had to look not a day over 30, and somehow the movie was more than able to pull it off. As it turns out, producing this scene would be no easy feat.

As a matter of fact, we came to learn that two actors were needed to pull off the time-jumping scene – Kurt Russell, who would act the scene, and a second, body-double actor, one more in the character's age range, who had to act out the scene just as Kurt Russell had before. This actor had the difficult job of mimicking a legendary actor's performance so that the visual effects team could merge the two together to create young Ego.

8 CHOOSING VOL. 2'S TRACKS

guardians-galaxy-2-full-team-header

James Gunn has always said that the music was an important part of Guardians of the Galaxy Vol. 2, and that the songs were written into the script. But did you ever wonder how the director chose all of those tracks for the volume 2 mix tape? Well, it turns out that was no easy work either, as we came to learn in the commentary of the movie.

In his computer, James Gunn had over 500 songs that he dubbed Meredith Quill songs -- music that he associated with the character of Peter Quill's mother. When he wrote the script, he would go through the songs, listening to them in order to find the perfect one to fit his scenes. If that isn't dedication and meticulous work to make a movie the best it can be, we don't know what is.

7 THE GAMORA/NEBULA FIGHT

Guardians of the Galaxy Nebula

Besides the relationship between Peter Quill and his fathers, the difficult rivalry between adoptive sisters Gamora and Nebula was at the heart of Guardians 2. That relationship reached a turning point when Nebula found Gamora on Ego, attacking her from the skies in a sequence we came to learn was inspired by Alfred Hitchcock's famous North By Northwest airplane attack scene.

The sequence was so raw and emotional, so revealing and cathartic and brutal that Gunn, uncharacteristically for a Guardians movie, didn't want any music in it; he wanted to have it play out with just the sounds of the scene itself. The sound of leaves rustling, of Nebula screaming and of weapons blasting set a different tone for the scene, one that made you feel all the pain and shared history between these two estranged sisters.

6 EASTER EGGS HIDDEN IN A PILE OF BONES

Guardians-2-BTS-pile-of-skulls

Before Guardians Vol. 2 kicks into its final gear, there comes a revelation -- the revelation that Ego isn't what he appears to be, that he is not only the father of Peter Quill but of countless more children that he used to try and take over the universe. Their dead carcasses are shown abandoned deep in the caves of the Living Planet, a literal pile of bones discovered by Gamora and Nebula.

While the scene comes as a ghastly shock, James Gunn actually used this moment to hide some Easter eggs. In fact, the director informs us in his commentary that there are some very, very “cool” Easter eggs to look for in those bones. Just what they are exactly remains a mystery, but all knowledgeable Marvel fans and hunters now know where to look.

5 NEBULA'S BIGGER ROLE

nebula-guardians-of-the-galaxy-vol-2-header

Guardians Vol. 2 was a busy movie, with many characters going through emotional arcs. But nowhere was this more true than with Karen Gillan's Nebula. Introduced in the first film as a one-note villain and threat to the Guardians, the character was given much more depth in the sequel, a movie that even saw her join the ranks of the team, and become a part of their family.

As it turns out, that was always part of the plan. In fact, in the director's commentary, James Gunn revealed that, when Karen Gillan had first been cast as Nebula, he had told her that it was for a small role for the first film, but that he intended for her character to become a Guardian of the Galaxy later on. That's right, even then, the director had long-term plans for the franchise and its characters.

4 NOT A PRODUCT PLACEMENT

Guardians-2-Dairy-Queen

While the bulk of Guardians Vol. 2 takes place in outer space, there are still a few elements of Peter Quill's home planet Earth that make it in the movie. For instance, the movie opens with a scene at a Dairy Queen, and it also ends with Kraglin giving Peter a Zune as a gift to replace his broken Walkman. While some were quick to complain about product placements in the movie, James Gunn shot those theories down.

Actually, both elements were used by choice. This particular Dairy Queen was used because it was one that was near and dear to the director's heart growing up in Missouri, and the Zune was used more for comedic purposes because one, an iPod would have been the too obvious choice, and two, because Star-Lord being completely awed at the fact that it contained (only) 300 songs was amusing. SUre, they wouldn't be in the movie without permission and DQ was definitely a sponsor, but it's nice to know there were legit reasons they were included.

3 A HUG BETWEEN SISTERS

movie nebula

The complicated relationship between Gamora and Nebula was given a new twist when it was revealed that Gamora, and not Nebula, was the “evil” sister -- that it was Nebula who wished to be loved by her sibling. So, at the end of the film, when Gamora realized what she had missed her entire life, she gave Nebula a hug. What happened next in the scene however, was something that wasn't scripted.

In fact, James Gunn revealed in his commentary that it wasn't originally planned for Nebula to ever-so-slightly hug her sister back with one arm. It was actually Karen Gillan's decision to add that, on the spot, and it was an action that Gunn admitted made him tear up instantly. It was a small gesture, but one that spoke infinite volumes, and gave the scene a whole new meaning.

2 THE ORIGINAL GUARDIANS

Original Guardians of the Galaxy

As the credits rolled on Guardians Vol. 2, longtime comic book readers were treated to a mid-credits scene that showed the reunion of Sylvester Stallone's Stakar, aka Starhawk, and the other “original” Guardians of the Galaxy from the comic books like Charlie-27, Krugarr and Martinex. However, while the characters appeared separately in the movie, it wasn't planned to have them meet.

In fact, the scene of these characters uniting once more to do what they do best wasn't in the movie's original script. James Gunn actually had this idea much later on, realizing that it would be a nice surprise for fans and a very cool development that could potentially lead to many more appearances of this new team of Guardians in future cosmic movies set in the MCU.

1 ADAM WARLOCK'S ROLE

One of the more important after-credits scenes of Guardians of the Galaxy Vol. 2 was the scene where we saw a very distraught Ayesha introduce her newest creation, Adam, marking Adam Warlock's long-awaited arrival in the MCU, a beloved character fans have been waiting for for a very long time. But, as it turns out, there was a time when Adam was supposed to be prominently featured in Vol. 2.

In his director's commentary, James Gunn revealed that Adam Warlock was in his original script for the movie, but that he ultimately had too many characters in the film. The choice came down to Warlock and Mantis, and Gunn ended up keeping the latter. But worry not, Adam Warlock fans, the character is coming for the third and final chapter of this sprawling space saga.

What did you think of Guardians of the Galaxy Vol. 2? Let us know in the comments!