SEOUL—Of all of them, he was the first one. They call him “The Man,” and Robert Downey Jr. is grateful at the end. “It’s all very gratifying,” he said.

Roles in a Marvel Cinematic Universe (MCU) can be career-defining for any actor, but in this case, it was Downey the actor who defined the MCU.

Downey was the most established actor—and thus the one who took the biggest risk—when he took on the role of Tony Stark aka Iron Man in the very first MCU film, 2008’s “Iron Man.” At the end of that film, an end credits scene showed Stark being recruited by Nick Fury (Samuel L. Jackson) into the “Avengers Initiative.”

Cut to the present, where the MCU is the biggest film franchise and Downey is now known most for being Iron Man. This is not surprising considering Downey has played Iron Man in eight films: “Iron Man” (2008), “Iron Man 2” (2010), “The Avengers” (2012), “Iron Man 3” (2013), “Avengers: Age of Ultron” (2015), “Captain America: Civil War” (2016), “Spider-Man: Homecoming” (2017), and “Avengers: Infinity War” (2018).

“Ten years later, now I can honestly say I’m glad to be part of this moment,” he said to reporters.

He talked about the long friendship he’s had with fellow “Avengers” actors, including Jeremy Renner, who was with him in Seoul, and about how the two of them had become fathers since joining the franchise. They first worked together seven years ago, in 2012’s “The Avengers.”

Last time viewers saw Tony Stark he was utterly defeated in outer space and unable to stop Thanos. In “Endgame,” he has to somehow return to Earth where he must deal with what to do next. Will he patch things up with Captain America?

After all this time playing Iron Man, Downey also faces a future without Tony Stark. His future projects include playing the doctor who talks to animals in 2020’s “The Voyage of Doctor Dolittle” and returning as the world’s most famous detective in the third “Sherlock Holmes” film in 2021.

But for now, he takes on last invincible bow as the character he’s known for the most: “Thank you to all the fans for enabling us to continue our friendships and careers for so long.” —RUEL S. DE VERA