It would take multiple Guardians of the Galaxy: Vol. 2 viewings to spot James Gunn’s multitude of Easter eggs and references. Thankfully, we have time to do things like that, and to compile lists like this one. Of course, there are so many references throughout the movie – even though it may not appear that way – so we’re limiting ourselves to just fifteen.

To make things even more interesting, we aren’t including certain scenes and sequences, such as the Adam Warlock tease, Stan Lee's greater MCU role, or even the Watchers.

Check it out, but keep in mind that there will be quite a few spoilers!

Guardians of the Galaxy

Prior to the movie’s release, rumor had it that Smallville's Michael Rosenbaum would have an important role in Guardians of the Galaxy: Vol. 2.  According to the rumor, the actor would play Quasar, a powerful cosmic superhero. James Gunn was not the only one to tease this character; we also heard this from the numerous journalists who visited the set. Michael Rosenbaum himself said that his character would be an important one.

As it turned out, Rosenbaum had just a very minor cameo as Martinex. This was still cool, though, since Martinex is one of the original Guardians of the Galaxy member from the comics.

Martinex was joined by Ving Rhames' Charlie-27, Michelle Yeoh's Aleta Ogrod, Krugarr, and a Miley Cyrus-voiced Mainframe.

Rocket's Eye

This wasn't exactly an Easter-Egg; it was more of a reference to the previous Guardians of the Galaxy movie. In that movie, when Rocket came up with a plan to stop Ronan, he said that he needed a cybernetic eye that belonged to one of the Ravagers. Of course, he was joking at the Ravager’s expense, and didn't actually get the eye.

In Vol. 2, Baby Groot is tasked with bringing Yondu his fin, and he comes back with various unrelated objects, including the cybernetic implant. So, although Rocket didn't get the eye when he first requested it, he got it in the end. This was too bad for the eyeless Ravager, who wound up dead at the hands of Yondu.

Again, this isn't an Easter-Egg, but it shows that James Gunn put quite a bit of effort into establishing continuity between the films.

Kronan Battle

This blink-and-you'll-miss-it scene takes place when Yondu, Rocket, and Groot jump across the cosmos, heading toward Ego. Along with certain other scenes, including Stan Lee’s cameo, the seemingly LSD-filled trip takes the heroes over a planet where two creatures are battling.

Given their rocky appearances and their gear, we can safely say that the fighters are Kronans. We already saw the God of Thunder quickly dispatch one  in Thor: The Dark World. Next up, director Taika Waititi will voice Korg, a Kronan who ends up being Thor’s ally, in Thor: Ragnarok.

Howard the Duck and Cosmo

While the Howard the Duck movie was one of the worst Marvel films to date, James Gunn breathed new life into the character in 2014’s GotG. In that film, he was part of the Collector's collection, but he was freed. In the current movie, he showed up early, on the same planet as Sylvester Stallone's Stakar.

Seth Green returned to voice Howard. He'll apparently be back again, as Howard the Duck is set to cameo in future cosmic Marvel movies.

Cosmo the Dog also made an appearance, so to speak. Like Howard, he was part of the Collector's collection in the first movie. In Guardians of the Galaxy Vol. 2, he showed up in a small still that popped up during the credits.

These little things keep the fans watching through the credits.

Berhert and Contraxia

When the Guardians fled the Sovereign fleet, they crash landed on what appeared to be an uninhabited, completely green planet called Berhert, which first appeared in a 1969 Incredible Hulk comic book issue. It was home to the Sagittarians, who unwillingly take part in a conflict between the Jade Giant and Galaxy Master.

The planet wasn't explored in the movie, but who knows?

While the Guardians were stranded on Berhert, Yondu makes his first appearance. He’s with a couple of courtesans in an area of extreme promiscuity on the cold planet of Contraxia.

Contraxia wasn't presented like this in the comics. The only thing the MCU version had in common with the comic book version was the dying sun (and we know that this isn't the way a sun dies"¦)

Eighties References

There were tons of eighties references in Guardians of the Galaxy: Vol. 2. We could make an entire list of just these tiny Easter-Eggs!

At the beginning of the film, Star-Lord's device warned him that the Abilisk was coming. That device was actually a Mattel Football game.

Then there was Star-Lord and Gamora’s Cheers dialogue. And Gamora mentioned Knight Rider, hilariously butchering David Hasselhoff's name, which was dropped again a couple of times throughout the movie. Star-Lord also name-drops Skeletor, Pac Man, and Heather Locklear.

We could even say that the Sovereign's battle stations were modeled after eighties arcade games, from sound effects to the Sovereign people’s reactions.

From this point of view, James Gunn outdid himself.

The Orloni are Everywhere

This reference also served to establish continuity between 2014’s film and this year's sequel.

When we first met the adult Star-Lord, James Gunn introduced a new race. No, we’re not talking about the apparently Korbinite skeleton we saw as Peter Quill danced; we’re talking about the space-rats known as the Orloni (Star-Lord kicked them and used them as microphones as he searched for the Orb).

It was also established that the Orloni could be found on Knowhere, and following that, these creatures seemingly became ubiquitous in the Andromeda Galaxy.

Apparently, they actually are everywhere, also appearing in Guardians of the Galaxy: Vol. 2. Whether during the fight against the Abilisk (during which the Orloni annoy Baby Groot, and one winds up as his horsie) or on Yondu's ship (where Baby Groot brings an Orloni, rather than the fin), James Gunn made it clear that we'll see them again.

The Lone Celestial?

Now things get a bit tricky. In the comics, Ego actually was a living planet. In the MCU, he called himself a Celestial, and added that he was the only Celestial. Given his lifespan, and his past as an explorer, we should believe him.

However, the first Guardians of the Galaxy film featured at least one more Celestial, Knowhere, which was actually the severed head of such a being. A second Celestial, Eson, wielded the Power Stone during the Collector's short history of the Infinity Stones.

Is there a connection between these three Celestials, given the fact that Ego said he was the only one? There could be one, especially if Ego also tried to use the Infinity Stones to take over the Universe, but was stopped and killed before succeeding in doing so. This could explain his coming into existence as a brain, especially if Eson's death came via beheading.

Sure, this is just a theory, but wouldn't it be great? To learn more, check it out in full here!

The Boltzmann Brain

Here’s something very interesting about Ego's story: He said that he awoke in the cosmos as a giant brain. He lived for millions of years and learned how to create the world around him, including a planet and avatars.

According to New Rockstars, all of this might be based on a real quantum theory known as the Boltzmann Brain (you need to watch this - 16:30 - and search for more info on the web). According to the theory, in the vastness of the universe, it’s more likely that every conscience on Earth exists separately from all of the others (without any interaction), and creates its own universe, than for the alternative (actual humanity, actual society) to exist.

This is a neat theory! It can be traced back to the pre-Socratic theory of solipsism, which states that one can be certain only of his existence. Nothing is certain outside of that.

We don't know if James Gunn actually had this in mind, but it’s still mind-blowing.

Eternity

This was yet another awesome Easter-Egg that could potentially become much more important within the MCU. When Ego revealed his plan to his son, and tried to convince him to join the cause, Ego touched his forehead. In that moment, Quill's eyes changed, becoming black with bright dots here and there. It looked as if he held the whole Universe in his eyes.

Apparently, that was exactly what was happening. In that moment, Peter was awestruck and uttered one word: Eternity. This wasn't the first time Eternity was teased in the MCU; that honor went to Ant-Man. And if Eternity, exists in the MCU as a cosmic entity, we could eventually see Death, as well.

Ego helped Peter catch a glimpse of Eternity using the same trick the Ancient One used on Stephen Strange before his first interdimensional trip. Pretty neat, right?

Meanwhile, on Earth

This could be seen as a huge plot-hole in the MCU: If Guardians of the Galaxy Vol. 2 took place before the Civil War, why was there no mention of the strange blue gooey stuff that threatened to swallow the Earth?

But that wasn’t the point, and we can explain it this way: Doctor Strange played with time itself, changing the timeline.

So then were were back on Earth. Leaving aside the catastrophic event the Guardians prevented, we saw that Peter's grandfather was alive and well, even though the goo almost swallowed him. This small cameo set up the perfect reason for Peter to return to Earth after coming to terms with his mother's death.

The Other Cameos

We should mention a couple more cameos, and that’s literally a couple, since James and Sean Gunn's parents were seen as soon as the blue goo dies. So this is a neat cameo.

But it isn't the only one. We already mentioned the original Guardians and very well-known actors who played them. In addition, David Hasselhoff appeared when Ego became angry at Quill.

Horror director Rob Zombie showed up as an non-credited Ravager (good luck spotting him). Jimmy Urine (Mindless Self Indulgence singer) portrayed one of the Ravagers (Halfnut) who betray Yondu, as did comedian Steve Agee (Gef).

So Guardians of the Galaxy: Vol. 2 was packed with cameos!

Grandmaster

We have to mention one more cameo: Guardians of the Galaxy Vol. 2 gave us our first look at Jeff Goldblum as Grandmaster! And since everybody stayed for the credits scenes, we assume that everybody spotted him getting jiggy.

Why did James Gunn make this reveal? Well, nobody knew. However, many said that Jeff Goldblum also shot a cameo that ended up on the Guardians of the Galaxy Vol. 2 cutting room floor. We might never know for sure, or we just might have to wait for the Blu-ray release.

Pac Man

This is the last cameo on this list, so to speak.

The first Guardians of the Galaxy movie broke the climactic-battle mold. Ronan was about to obliterate everyone on Xandar, and Star-Lord distracted him with one of the most idiotic/genius moments in comic book movie history: a dance-off.

So did James Gunn outdo himself yet again with the Guardians of the Galaxy: Vol. 2 climactic battle? Unfortunately, he didn’t. However, his genius was obvious when Peter Quill conjured up a giant Pac Man to temporarily defeat his father (thus making good on a promise that he’d build a giant Pac Man with his godlike powers).

It was awesome! But, maybe, it would have been even more awesome if he had created a giant Heather Locklear.

Zune

Microsoft might have disapproved, but Guardians of the Galaxy: Vol. 2 featured a Zune player that was a gift from Kraglin to Star-Lord after Ego destroyed the latter's precious Sony player. Apparently, everybody on Earth had a Zune.

All joking aside, this was also a signal that Guardians of the Galaxy 3 will be a different kind of movie. If James Gunn wrote the first two scripts with the soundtracks already in mind, he'll have to change his method, since the Zune can store an amazing 300 songs.

We'll wait and see how the Zune affects the family theme in the third movie.