Way back in 2008, a single, flawed guy stepped forward to kick off the MCU as we know it. Without Iron Man there would be no Avengers – Tony Stark has been the lynchpin holding the team and franchise together from the start.
Genius, billionaire, playboy, philanthropist… It's tough to say goodbye, so we're looking back at some of the amazing, character-defining moments on Tony's journey to becoming Marvel's greatest hero.
"I am Iron Man" - Iron Man
Four little words that changed everything for the MCU. The dramatic delivery was peak, attention-stealing Stark. But revealing his heroic alter-ego allowed Tony to do so much more for New York, Earth, and - much later - the entire universe.
No more nukes - Iron Man
An earlier announcement started Tony Stark's heroic journey. Returning from a traumatic experience with knowledge of the damage his own weapons were causing, Tony goes up against mentor and movie bad guy Obediah to announce to the world that Stark Industries won't be making any more weaponry - all while snaffling on a much-needed cheeseburger.
The Battle of New York - The Avengers
Tony flies straight into a hole in space to save New York and the Avengers from a nuclear explosion. Enough said.
To suit or not to suit - Iron Man, Iron Man 3 and more
Several suit-related moments in one here in an attempt to answer Captain America's question - who is Iron Man without his suit? While the man of iron first materialised in a far away cave, he truly took to the skies to become Iron Man with the Mark II's first flight.
But in Iron Man 3, Tony finds himself without a suit and up against odds that would be insurmountable for an ordinary man. The legacy of The Battle of New York spills over into this movie, and Tony is struggling with PTSD and seriously lacking in self-worth. But we all know that Iron Man isn't the suit - it's Tony's brilliant mind and eternal tenacity that make him a hero. With that alone he manages to break his way into the Mandarin's mansion.
Tony vs Cap and Bucky - Avengers: Civil War
It doesn't matter which team you were on for Avengers: Civil War - the climactic three-way fight between Iron Man, Captain America and The Winter Soldier was a powerful moment. Two former friends beating on each is always going to be an emotional watch, but seeing Tony stand his ground when outnumbered took it to the next level.
Tony vs Thanos - Avengers: Infinity War
Tony steps into the breach again in Avengers: Infinity War for a seemingly useless attempt to defeat Thanos one-on-one. "All for a drop of blood," the villain scoffs, but it's another demonstration of Tony's willingless to stand up when all seems lost … which will spell the end for Thanos later.
Dad mode: activated - Spider-Man Homecoming, Avengers: Endgame
Tony becomes a major part of Peter Parker's life after the events of Civil War, appearing in a mentor capacity and laying the smackdown after the Staten Island Ferry incident in Spider Man Homecoming. This makes Peter's loss at the end of Infinity War all the more heart-wrenching, and lays the groundwork for seeing Tony as an actual father five years after the snap. He now has so much more to lose in an attempt to bring half the universe - including Peter - back to life.
Proof that Tony Stark has a heart
Opening up to Pepper Potts is arguably one of Tony's bravest acts. Doing so took him from billionaire playboy to hero to father, and made him a better man all round.
The final sacrifice - Avengers: Endgame
According to Doctor Strange, there was only one chance to save the day in Avengers: Endgame. And Tony took it, sacrificing himself to use the Infinity Gauntlet in a move he could never survive.
Pepper's "you can rest now" line was particularly gut-wrenching. Despite his reservations at the beginning of the film - valid given that he was one of the few to survive the snap with family intact - Tony has always wanted to do the right thing to save the people he cares about, and the world. He ended up saving the entire universe.