Cosmo the Space Dog
The first word that Cosmo - the Soviet-era space dog member of the Guardians - could be appearing in the film elated many, although the story had enough to deal with without bringing a psychically-gifted canine in to the picture. James Gunn left the door for a future appearance open, choosing to include the dog in the Collector's belongings, and making sure it escaped the disaster that (presumably) either killed or freed many other imprisoned specimens.
Not every entry in the Collector's... collection points to the future, though: in the bottom-left corner of one shot, a Chitauri soldier is unmistakably recognizable. It's unclear if the soldier was present during the attack on New York City seen in The Avengers or was captured by other means. But whatever reason the Collector has for keeping him locked up, he's far from alone.
It's impossible to miss the Dark Elf - one of the antagonists of Thor: The Dark World - as the Collector's assistant (Lovibond) is shown cleaning its cage. This creature's inclusion in the collection makes a bit more sense, as one of an ancient race believed to be completely eradicated by the Asgardians.
Proving that it wasn't just elements of the Marvel universe that the Collector was keen on keeping safe, the alien parasites that acted as the villains of Slither - James Gunn's directorial debut - can also be seen. During the first encounter with the Guardians and the Collector, several can be seen slithering across the inside of a glass display case.
Fan discussion was ignited when the mid-credits scene for Thor: The Dark World revealed some of the film's characters traveling to see the Collector (Benicio del Toro) with one of the oft-talked about Infinity Stones. For contained in the character's collection was a strange cocoon, bearing a strong resemblance to the one which housed Adam Warlock in the comics.
Given his prominent role in the original story surrounding Thanos and his Infinity Gauntlet, the inclusion was no accident. In Guardians, it's once again featured (not quite as) prominently, but the devastation wrought by the gem's detonation blows the cocoon apart. Could Warlock have escaped...?
Rob Zombie Ravager
After lending his vocal talents to James Gunn for both Slither and Super, rocker-turned-filmmaker Rob Zombie once again voices the role of the Ravagers' navigator. It's a small cameo that most will miss entirely, but clearly a tradition that Gunn is intent on keeping alive.
Fans of The Avengers will recall an early scene in which Tony Stark (Robert Downey, Jr.) tells Pepper Potts (Gwyneth Paltrow) to take some credit for the creation of Stark Tower: "give yourself...12% of the credit." The number is absurd to Pepper, later telling Tony that she was "having 12% of a moment" when they're later interrupted.
James Gunn keeps Joss Whedon's joke going, with Star-Lord informing the rest of his team that he has a plan for the film's third act. Well, 12% of a plan. The idea is once again ridiculous to Rocket Raccon (Bradley Cooper), with Gamora (Zoe Saldana) explaining that 12% isn't a plan - it's "barely a concept."
The dancing Groot seen in the first mid-credits sequence was an instant hit with fans, but few may realize that the dancing isn't purely the work of animators. Director James Gunn has since revealed that while he didn't perform the motion capture for the plant, those are, indeed, his dance moves used as inspiration.
Howard the Duck
We've already gone into great detail about the film's post-credits button scene, but fans of comic book character turned film star 'Howard the Duck' had what is certainly the most shocking reference to the character seen in decades. Director James Gunn has already warned that fans shouldn't put too much stock into his cameo though (apparently voiced by Seth Green) - it's all in the name of fun.
It's always hard to swallow when a performer on set ends up digitally painted over, with even their voice removed from the finished film. But with Bradley Cooper selected to give Rocket Raccoon a voice, the actor on set - James Gunn's brother, Sean - did get a chance to show his (actual) face on film. He also plays Kraglin, the right-hand man of Yondu Udonta.
Gunn's performance and chemistry with the crew is certainly preserved in some sense as well; for instance, he improvised the "jackasses standing in a circle" himself.
Given that the walking tree known as Groot would be a largely digital creation, the question of who would give the alien being its voice (and catchphrase) was one of the last to be officially answered. When director James Gunn finally confirmed that Vin Diesel - known for his action roles - had landed the part, fans were quick to point out that the actor had also lent his voice to the title character in Brad Bird's The Iron Giant (1999).
Having one heartwarming role with few words to his credit already, the biggest surprise came when Diesel returned to the booth fifteen years after bringing a hulking robot to life, and came face to face with Doc Kane, the same sound engineer he had worked with on The Iron Giant. Clearly a strong omen, but what are the odds?
Besides being tasked with breathing personality into the words "I am Groot" (a task which, surprisingly, was more successful than expected) Vin Diesel was also tasked with performing the signature line in multiple languages. That means a delivery of the line with different emotions in English, French, Portuguese, Mandarin, and more - the actor's first multilingual performance.
Those are all the easter eggs, bits of comic book trivia, and subtle references fans can look out for on repeat viewings of Guardians of the Galaxy, but if you have any that have been missed, please share them in the comments.
If you’ve seen the movie and want to discuss details about the film without worrying about spoiling it for those who haven’t seen it, please head over to our Guardians of the Galaxy Spoilers Discussion.
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