In many ways, Robert Downey Jr.'s depiction of Tony Stark helped launch the Marvel Cinematic Universe as we know it. Since the original Iron Man dropped in 2008, RDJ has reprised the role on nine separate occasions, with a tenth on the way with Avengers: Endgame. And while the character has certainly enjoyed a triumphant run, all good things must come to an end. Reports have already run rampant, indicating that Endgame will be Robert Downey Jr.'s last time donning the signature costume. 

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While it has yet to be officially confirmed, it seems possible for a variety of reasons. For one, his contract with the MCU is coming to an end, which means the studio giant would have to re-up accordingly. On the creative side, what's best for the overarching story should be considered. We've already seen Tony toy with the idea of self-sacrifice, and it wouldn't be surprising to see him give his life in the name of defeating Thanos. It would certainly be a fitting end for the billionaire playboy-turned-hero, and one that would resonate with his loyal fans.

Of course, it's equally possible that Marvel decides to extend the contract. After all, cutting ties with Iron Man would be a big move for the franchise. Still, it's a testament to how far they've come, and can their new wave of superheroes thrive if they remain anchored by the old guard?