MCU star Robert Downey Jr. reposts an Avengers: Endgame set video of the cast singing "Happy Birthday," revealing the clip is not about Thanos actor Josh Brolin - not Iron Man. Though Avengers: Endgame came out close to a year ago, it's very much still on fans' minds. It's to be expected, as the movie marked the end of the Avengers as we know them, with both Downey Jr. and Captain America's Chris Evans completing their Marvel contracts. Luckily, new heroes like Dr. Strange, Black Panther, and Captain Marvel are there to pick up the slack.

Avengers: Endgame was a massive success both critically and commercially, even besting Avatar as the top box office earner of all time. Many applauded the film for wrapping up the stories of so many characters in an emotionally satisfying way. The movie was drawn back into the spotlight this past December with the release of Star Wars: The Rise of Skywalker. Like Avengers: Endgame, that film marked the end of a long saga of films, in this case over decades. This inevitably led to comparison between the two. While reception to Rise of Skywalker was more mixed than that of Avengers: Endgame, there are still many who found both films to be satisfying conclusions.

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On Instagram, Downey Jr. shared an old video of members of the Endgame cast, including Downey, Chris Hemsworth, and Paul Rudd, singing "Happy Birthday" to Brolin. Last year, Downey posted a (briefly) shorter version of this same video to commemorate Iron Man's anniversary. As it turns out, the video was about Brolin all along. Check it out in the space below:

With the conclusion of the Infinity Saga behind it, Marvel is now focusing on Phase 4 of the MCU, which will feature two movie releases this year. First up will be the long-awaited Black Widow film, with Scarlett Johansson, Florence Pugh, and Rachel Weisz. There's also a possibility that Downey Jr.'s Iron Man appears, as the film is set prior to both Tony and Natasha's deaths. Following Black Widow, Marvel will release The Eternals, an ambitious story set across various time periods in history. Marvel also has its MCU shows in the works at Disney+, several of which will be a part of Phase 4.

Despite the excitement over what's to come in the MCU, it will be a long time before fans see a Marvel movie with the scope of Avengers: Endgame. Audiences are understandably still excited about behind-the-scenes content from the film. This is especially the case for videos like this one that include so much of the cast. Brolin's character Thanos probably just wanted the Infinity Gauntlet for his birthday, but hopefully a song from the Avengers sufficed.

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Source: Robert Downey Jr.