Kevin Feige has spent 11 years supervising the construction of the Marvel Cinematic Universe, brick by brick, to the point where it has become an enormous universe. The fact is, in terms of sheer volume, the twenty movies that have been released since Iron Man make up less than half of the MCU. Although not as critical to the universe as the movies, most content can be found outside the movie theatres. At the time of writing, there are eleven tv shows, five one-shots (short films), two digital series, and twenty-one tie-in comics under the "it's all connected" mantra.
With that said, the MCU still mainly revolves around the Avengers, the Infinity Stones, and Thanos. These other sources of content do, however, provide a few interesting nuggets here and there, unraveling the mysteries of this immense universe.
10 THE MANDARIN IS ALIVE
Iron Man 3 is maybe the most divisive movie in the MCU because of its portrayal of the Mandarin, Iron Man's most popular comic book villain. Revealing that Ben Kingsley was actually playing an actor pretending to be the Mandarin was a bold move. Moviegoers were then led to believe the Mandarin never actually existed, and that it was Aldrich Killian the whole time.
But then Marvel released All Hail The King, a short one-shot showing Kingsley's character be threatened by the people who worked for the real Mandarin. It was a revelation that excited many fans, who hoped to finally see a faithful adaptation of the villain on screen in the future. That was 13 movies ago.
9 CHARACTERS' FATES POST-SNAP
Infinity War saw a lot of heroes turned to dust, but not even a movie as big as this can make space for every character in the universe. A ton of secondary characters were left out, as they would probably not have added anything to the overall plot. However, after the movie's release, many questions were asked concerning the fates of those heroes, and many were answered.
The Russo brothers were gracious enough to spill the beans on a handful of people who had survived and who had died in the Decimation off-screen. The confirmed survivors are Nakia, Aunt May, Valkyrie, Pepper Potts and (for some reason) Howard the Duck. Lady Sif, Betty Ross, and the character Matt Damon played in Thor: Ragnarok were the victims.
8 COULSON IS ALIVE
One of the most heartbreaking scenes in The Avengers was Phil Coulson's death at the hands of Loki. It was a crucial moment in the story, as it motivated the team to stop the God of Mischief once and for all. But comic book deaths are rarely permanent. Sure enough, Clark Gregg was back reprising the role of Agent Coulson a year later, in the first episode of Marvel's Agents of S.H.I.E.L.D. And he's been alive and well for over five years now (SPOILER ALERT), until his recent supposed death, that is.
Although he's been around for quite some time, the movies have never addressed it, meaning the Avengers still believe Coulson is gone for good. For all we know, that might all change in Avengers: Endgame, according to one fan's theory.
7 J.A.R.V.I.S' ORIGIN STORY
J.A.R.V.I.S was one of the first characters to be introduced to the MCU. Tony Stark's British-tongued AI assistant was essentially his master's most trustworthy companion. Iron Man shared everything with his artificial friend, (until he morphed into Vision). But J.A.R.V.I.S isn't just a funny acronym (Just A Rather Very Intelligent System). It is actually an homage to Howard Stark's former butler Edwin Jarvis.
Edwin Jarvis is a prominent character in the intertwining stories of Howard Stark and Peggy Carter and features heavily throughout both seasons of Agent Carter. Additionally, In Iron Man 2: Public Identity, (the tie-in comic to the movie), it's revealed that after the Starks passed away, the English butler became a father figure to Tony until his very own death.
6 FURY FAILS TO ASSEMBLE THE AVENGERS
Nick Fury is the backbone of the Avengers. He achieved the impossible when he successfully united a monster in hiding, a god from another planet, a soldier from the 1940s, and a narcissist who refuses to follow orders. He then successfully brought them all back years later to defeat Ultron. Unfortunately, Infinity War failed to bring them all together again, and that did NOT end well.
However, the Captain Marvel prelude comic brought some interesting facts to the table. It shows Fury and Hill, who had been missing since Age of Ultron, trying to reconcile things between Tony and Steve. It came to nothing, as Captain America told Fury exactly what Iron Man told Hill. There was currently nothing in need of avenging.
5 COULSON BEGAN AGE OF ULTRON... AND ENDED IT
Agents of S.H.I.E.L.D is the show most closely connected to the larger Marvel universe. Winter Soldier revealed Hydra had been inside S.H.I.E.L.D since its foundation, which became a pivotal plot point for the show. That was after we saw the agents cleaning up the mess Thor left behind in The Dark World, and before we saw them dealing with the Sokovia Accords and preparing for the coming of Thanos. But only the movies had any impact on the show, not vice versa. With one exception.
Towards the end of season 2, Coulson references something called the Theta Protocol. This protocol is later revealed to be the codename for the helicarrier that saves the Avengers in the Battle of Sokovia. Before that though, there is an even stronger connection. One episode ends with Coulson calling Maria Hill to tell her he's found Loki's scepter, before delivering his last line of dialogue. "Time to call in the Avengers".
4 THE SUPERIOR INFINITY STONE
The Infinity Stones are the center of the entire story of the MCU. Throughout the course of the franchise, they've quietly snuck into view, one after another. But one stone remained hidden right until the end. The soul stone finally made its appearance in Infinity War, but even now, its true power is still pretty much unknown. The Infinity War prelude comic, however, was the first to mention the soul stone by name and to reveal its most important aspect.
The comic book sees Wong teaching Doctor Strange about the Infinity Stones. When he arrives at the mysterious orange-tinted gem, he states it is the biggest threat of them all, basically telling the audience it is Marvel's version of "The One Ring to Rule Them All".
3 NO WAR MACHINE IN NEW YORK
After The Avengers fans wondered why, after becoming a valued hero in Iron Man 2, War Machine failed to make an appearance in the Battle of New York. This was answered in the Iron Man 3 tie-in comic. Colonel James Rhodes was undergoing a mission of tracking down the Ten Rings organization when he was contacted by Tony Stark to help him "fight some aliens" in New York.
Unfortunately, the mission was taking place on the other side of the planet, in Hong Kong, so there was no way Rhodes would be able to make it to the Big Apple in time. The comic issue does reveal he joins the Avengers for Shwarma after, so not all was lost.
2 HAMMER AND ABOMINATION
Two names that have been forgotten by many are the ones of Justin Hammer, Tony Stark's rival businessman and Emil Blonsky, AKA Abomination, a soldier turned monster who confronts the Hulk. Both of them survived their early appearances but quickly disappeared from the face of the MCU. With that said, Marvel has been kind enough to give us evidence of their continued existence.
In The Consultant one-shot, S.H.I.E.L.D reveals the Abomination had been taken into custody. An episode of Agents of S.H.I.E.L.D later reaffirmed that statement and added the fact he was in a cell in Alaska. Hammer was also taken into custody in Iron Man 2 and was then mentioned years later in the least probable place. Netflix's Luke Cage showcased a group of criminals using Hammer Industries weapons, subtly letting the audience know he was still out there.
1 RUSSIAN SPIES AND BRAINWASHED ASSASSINS
Agent Carter didn't last long, having only been on the air for two seasons. But with Hayley Atwell reprising the role of Steve Rogers' long-lost love Peggy Carter, there were bound to be some important connections to the MCU. In the first season of the show, the beginnings of the Black Widow and Winter Soldier programs were introduced. In it, Carter infiltrates the Red Room Academy, a school for young girls training to be assassins. 70 years later, Natasha Romanoff is haunted by memories of this very place.
In the final episode of the first season, fans were graced with a surprise cameo by Arnim Zola, Red Skull's former right-hand man. The season ends with Zola offering Doctor Fennhoff, a man with the ability to control minds, a job at Hydra. The writers revealed that Zola was referring specifically to the Winter Soldier program.