It might be hard to believe, but it's been about 10 years since the first Avengers movie hit cinemas, all the way back in May 2012. While it certainly wasn't the first MCU movie, it did represent an important step for the series in that it brought together half a dozen heroes to form a team to take on a potentially world-ending threat together.

RELATED: How the MCU Was Made: ‘Marvel’s The Avengers’, Recasting Hulk, and How That Thanos Scene Happened

Everything fell into place, miraculously, and The Avengers became a huge critical and financial hit. It was popular enough with audiences that it grossed over $1.5 billion worldwide, which puts it in the top 10 highest-grossing movies of all time (at the time of writing). 10 years on, it's clear there are more than 10 reasons why it worked so well, but nonetheless, here are 10 of the biggest reasons why the first Avengers film remains one of the MCU's best entries.

The novelty of a team-up

The Avengers assemble in New York City

In 2012, the idea of different characters who'd (mostly) had their own films to establish each of them was quite the novelty, and maybe even groundbreaking. Sure, the 1930s Universal Monsters series had done a few crossover movies with their iconic characters decades ago, but nothing on the scale of The Avengers.

In The Avengers, the threat posed by Loki's alien invasion made it necessary for the six main heroes to come together and save the earth together. While crossovers had been a common occurrence in comic books, it was mind-blowing to finally see one take place onscreen. And even if Infinity War and Endgame have pushed the concept further, with dozens of heroes crossing over, it's important to remember in 2012, even just six of them being together was a big deal.

The humor & light tone

The Avengers (1)

Sure, the concept of a Marvel movie being funny wasn't invented in The Avengers. But here, the banter-heavy screenplay, snarky characters, and numerous jokes sprinkled throughout the film helped push the idea that these superhero movies could function as action comedies.

It paved the way for other MCU films to embrace comedy wholeheartedly, like Guardians of the Galaxy, Thor: Ragnarok, and Spider-Man: Homecoming. Pus, in The Avengers, the humor contrasts with the high stakes storyline and makes the emotional moments hit much harder, like the scene where Agent Coulson's killed, which remains one of the saddest deaths in the MCU (even if he got better).

The infighting (verbal and physical)

Hulk Fighting Thor

While Tony Stark has always been snarky, most of the other characters get a good upgrade in snark here, too. Even if the squabbling and quips at the expense of other characters have been criticized as a crutch in more recent MCU films, it was pulled off well here, and still felt fresh in The Avengers.

RELATED: The Greatest Marvel Movie Action Scenes, Ranked

Even more exciting than the verbal sparring, though, was that The Avengers gave viewers a chance to see the heroes physically square off against each other, including a skirmish with Thor, Captain America, and Iron Man, and a fight between The Hulk and Thor. While it's fun to see them fight as a team by the film's end, it is also very entertaining to see them briefly go up against each other.

The pacing

Avengers fast pacing

The Avengers is a fast-paced, relentless film that remains consistently entertaining over almost two and a half hours. There's always a great deal happening, and it manages to remain a breezy, engaging watch without feeling overstuffed or rushed.

The main way it pulls this off is by building upon the characters already introduced in the MCU's previous films. As the audience already has a grasp on most of them, the film can hit the ground running without having to set everything and everyone up from scratch. It takes advantage of the previous films beautifully, and ensures that this original team-up movie can be a breathless ride from beginning to end; all killer and no filler.

The villain

Loki in The Avengers (2012)

When he was introduced as a villain in 2011's Thor, Loki failed to make a big impact. He was a decent enough foil to his brother, Thor, but came across as a little too whiny and annoying, and far from as charismatic or scheming as he could be.

With The Avengers, that changed. He may not be the most terrifying villain in the MCU (though he does kill Coulson here, to be fair), but this film cemented him as one of the franchise's most memorable. Tom Hiddleston shined and made the character a lot of fun to hate, leading to the immensely satisfying smack-down he gets - courtesy of The Hulk - at the film's end, which stands as one of the best moments in the whole movie.

The Hulk

Mark Ruffolo-Hulk-The Avengers

Before The Avengers, there was a struggle to depict the character of the Hulk properly, in the world of film. Ang Lee's 2003 take on the character was as interesting as it was divisive, and Hulk's first outing in the MCU, in 2008's The Incredible Hulk, was a bit of a forgettable mess.

When the character of Bruce Banner/Hulk was recast from Edward Norton to Mark Ruffalo, things finally clicked, and it led to the first movie version of the character that the vast majority of viewers liked. Ruffalo nails the sheepish, nervous energy of Banner perfectly, and had excellent chemistry with the rest of the cast - particularly Robert Downey Jr - to boot.

The action

The Avengers action

Viewers can rely on solid action - and plenty of it - when it comes to the films in the MCU, and The Avengers is no exception. Part of its fast pace comes from just how much action there is, from the heroes fighting amongst each other, to the attack on the helicarrier, to the extended battle that takes up much of the film's final act.

Maybe it's quantity over quality, but it's all largely satisfying, and the numerous action sequences enable each hero to show off their powers and skillsets (yes, even Hawkeye). And seeing them combine their powers while working together during the big fight at the end? Very satisfying stuff.

It's bright/colorful

Avengers daylight

Besides some murky night scenes early on, The Avengers is a refreshingly bright and colorful film. As a result, it's easy to look at, and it does stand out from some of the more dimly lit superhero movies that are shrouded in darkness.

It suits the lighter, breezier tone of The Avengers, and solidifies it as a visually pleasing, accessible action-packed blockbuster. It's particularly refreshing to see the final battle sequence take place in the daylight (because as great as the final battle in Endgame might be, it's pretty dark, murky, and hard to see what's going on at certain points).

The set-ups

Avengers Thanos (2012)

There were neat end-credits scenes for future films in MCU movies before The Avengers, but it's hard to deny that it had one of the best. Viewers get a glimpse of Thanos for the first time, setting in motion a character who would become the greatest villain in Marvel's first three phases, and one of its most memorable characters full-stop.

RELATED: Every Marvel Cinematic Universe Credits Scene Ranked

Then there's the fact that so many things that happen here become essential for other films going forward. The final battle ties into future Captain America movies, Iron Man 3, and Spider-Man Homecoming, and events from the film are revisited via time travel in Endgame (during which, Loki's spin-off show is set up). Just as plenty of films built up to The Avengers, plenty of movies that followed built off of it, too.

The shawarma

Avengers shawarma

Love it or hate it, you can't deny the shawarma post-credits scene is one of the most memorable in the entire series. The heroes, after their battle, sit in silence, too tired to do anything but eat, after Tony Stark makes good on his promise to take them to his favorite shawarma restaurant.

Beyond being funny, and sort of poking fun at the idea of a post-credits scene, it also humanizes the characters. Usually, a film ends as soon as its final fight ends, but here, we see the heroes recharging and recovering, as they would. They're all (mostly) human, after all.

NEXT: What Dayjobs The Avengers Would Have, According To Reddit