It's almost impossible to believe, but it has been an entire decade since Robert Downey Jr. made his debut as Tony Stark aka. Iron Man, launching what we now know as the Marvel Cinematic Universe. In that ten years, heroes have fallen, galaxies have been saved, earth has been avenged (on numerous occasions) and the Marvel Cinematic Universe has grown to become the most beloved cinematic franchise of all-time.

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Looking back at the entire Infinity Saga, which started with 2008's Iron Man and ended with 2019's Spider-Man: Far From Home, it's undeniably clear that there's an immeasurable number of iconic and memorable moments, but it's fair to say that some scenes defined the franchise more than others. To celebrate the first ten years of Marvel movies and the conclusion of the Infinity Saga, we're discussing and ranking ten moments/scenes that define the tone, style and voice of the Marvel Cinematic Universe.

Thor Arrives In Wakanda - Avengers: Infinity War

Thor Arrives In Wakanda - Avengers Infinity War Cropped

The Marvel Cinematic Universe is full of exciting and epic action sequences, but only a few compare to Thor's heroic arrival in the final act of Avengers: Infinity War. Just when it looked like The Outriders might defeat Captain America, Black Panther and the other Avengers, Thor and his Guardian allies arrive in epic fashion. Possibly more than any other scene on this list, Thor's bombastic arrival in Wakanda defines how ridiculously big and bombastic the Marvel Cinematic Universe can be.

Guardians vs. Ronan - Guardians Of The Galaxy

Before the release of James Gunn's Guardians Of The Galaxy, fans were unsure if the cosmic side of the Marvel Cinematic Universe would work on the big screen. The final act of the film, however, proved that Marvel can make even the weirdest of characters work, as Star-Lord, Gamora, Rocket and Drax unite to wield an Infinity Stone and defeat Ronan. Taking the franchise in a bold new direction, this scene more than any other defined the cosmic corner of the MCU.

You've Become A Part Of A Bigger Universe - Iron Man

It's hardly surprising that a scene that defined every Marvel film after Iron Man came after the credits had rolled. Hidden in the credits of Jon Favreau's Iron Man was a wonderfully exciting scene that introduces Nick Fury and revealed Marvel's plans for an interconnected universe of movies, establishing what we now know as the Marvel Cinematic Universe.

Iron Man's Sacrifice - Avengers: Endgame

Robert Downey Jr. as Tony Stark aka. Iron Man in Avengers: Endgame

It's often the most heartbreaking moments that define a particular movie or, in this case, an entire cinematic franchise. With The Avengers doing everything in their power to defeat Thanos' army and stop the mad titan from winning for a second time, Iron Man gets his hands on the Infinity Stones and sacrifices himself to save the universe. It's hard to predict how Tony's death will impact the Marvel Cinematic Universe, but it would be safe to assume that the loss of Iron Man will define every phase of the MCU moving forward.

Avengers Assemble! - Avengers: Endgame

Captain America stands with the rest of the Avengers behind him ready for battle

When discussing scenes that define the Infinity Saga, it's impossible to ignore the already iconic "Avengers Assemble!" moment from Avengers: Endgame. After ten years of interconnected movies and stories, it was incredibly fulfilling to see every conceivable hero stand alongside Captain America and fight Thanos' army. Displaying exactly how powerful and epic the Marvel Cinematic Universe can be at its best, this scene is undoubtedly one of the Infinity Sagas most defining moments.

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Thanos Has Entered The Building - The Avengers

In a scene that shows just how big Kevin Feige and Marvel Studios' plans for the Marvel Cinematic Universe were, we see Thanos (not portrayed by Josh Brolin) for the very first time as he smirks at the camera after being told that challenging The Avengers would be courting death. Despite being an extremely short end credits sequence, this scene introduced Marvel's biggest villain and essentially defined the narrative for the next two phases of Marvel Cinematic Universe movies.

The Snap - Avengers: Infinity War

Avengers Infinity War the Snap

In what is arguably the most shocking scene in Marvel movie history, earth's mightiest heroes lose their battle against evil as Thanos snaps his incredibly large fingers, ending half of all life in the universe. More than perhaps every scene/moment on this list, the snap shows exactly how far Marvel is willing to go to surprise audiences and while we're still seeing how this scene impacted the MCU, it's already one of the most iconic and memorable moments the franchise has ever delivered.

Captain America vs. Iron Man - Captain America: Civil War

In what can only be described as one of the Marvel Cinematic Universe's most heartbreaking action sequences, Captain America and Iron Man finally come to blows. Unlike previous fights between the two heroes, however, this confrontation was a brutal and outrageously violent fistfight, that left the Avengers fractured and the earth vulnerable. Taking the franchise's central heroes in a shocking new direction, this scene changed the MCU forever and its impact can be felt in every new installment of the franchise.

I Am Iron Man - Iron Man

Following his explosive and undeniably awesome battle against Obadiah Stane aka. Iron Monger, Tony Stark holds a press conference to protect his secret identity. Instead of sticking to the planned cover story, however, Tony reveals to the press and the entire world that he is, in fact, Iron Man. It might look and sound like a throwaway moment, but this outrageously playful scene went against expectations and standard superhero conventions, defining the tone of the MCU moving forward.

Avengers Assembled - The Avengers

It's hard to beat seeing the original six Avengers assemble for the very first time! As Loki and Thanos' Chitauri army brings death and destruction to New York in an attempt to take control of the planet, earth's mightiest heroes overcome their differences and finally assemble to save the day. this incredibly exciting shot, which circles the entire team of heroes as Alan Silverstri's appropriately epic theme rises, shows how epic and grand the Marvel Cinematic Universe can be and set the bar for every installment of the franchise moving forward.

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