So. Many. Details.
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There’s a blue Tobias Fünke visible in The Collector’s museum.
The Russo brothers, who directed Avengers: Infinity War, also directed episodes of Arrested Development in the past.
Netflix / Marvel Studios
Before sending Hulk back to Earth in Avengers: Infinity War, Heimdall says, “All-Father, let the dark magic flow through me one last time.” This is a reference to what Loki says to Thor when he arrived on earth in the first Avengers movie.
Damn, these callbacks.
Marvel Studios
Rocket seems to have a thing for limbs. In Guardians of the Galaxy he jokes that he needs some guy’s prosthetic leg and in Avengers: Infinity War he asks Bucky, “How much?” for his new arm that Shuri built.
LOL.
Marvel Studios
Rocket also has a thing for eyes. He mentions taking eyes in both Guardians of the Galaxy movies, and he gives an eye to Thor in Avengers: Infinity War.
Double LOL.
Marvel Studios
The old flip phone Tony Stark has is the one Steve Rogers left for him at the end of Civil War in case he ever needed him.
In case you were wondering.
Marvel Studios
Marvel
Red Skull was played by Ross Marquand, who also plays Aaron on The Walking Dead.
In case you were wondering if it was Hugo Weaving (who played Red Skull in Captain America: The First Avenger).
Marvel Studios / AMC
Marvel / HBO
In the beginning of the movie Loki says, “We have a Hulk,” the famous line Tony said to him in 2012’s The Avengers.
It’s a good line, to be fair.
Marvel Studios
Marvel Studios
The Hulk crashing Doctor Strange’s place to warn him and Wong that Thanos is coming is much like in the Infinity Gauntlet comic, except it’s the Silver Surfer who comes to inform him.
Marvel Comics / George Perez / Ron Lim / Via marvel.com
The snap by Thanos that kills half of the universe happens in the Infinity Gauntlet comic as well.
Marvel Comics / George Perez / Ron Lim / Via marvel.com
The scars from Doctor Strange’s surgery were very visible on his hands when he gave Thanos the Time Stone.
Marvel
Peter Parker (who has Spidey-sense) and Mantis (who has empathy powers), both realized something was wrong before disintegrating. Peter says, “Mr. Stark, I don’t feel so good.” and Mantis says, “Something is wrong.”
Marvel Studios