Marvel fans react as Robert Downey Jr makes shock Avengers return as Doctor Doom

Downey took to the stage in Hall H wearing the Doctor Doom mask and outfit in front of hundreds of stunned Marvel fans, going on to say: "New mask, same task."

It was also revealed that Infinity War and Endgame directors Joe and Anthony Russo will return to helm the two new Avengers movies, with the former of the films retitled from The Kang Dynasty to Doomsday.

Now, fans have been reacting to the news of Downey's casting as Doctor Doom, with plenty excited at the prospect of seeing him back in the MCU.

"Marvel bringing Robert Downey Jr back as Doctor Doom is epic," one wrote on X. "That guy IS Marvel. I guess he's gonna play a version of Tony Stark as Doctor Doom in another universe. Can't wait!"

Another said: "Robert Downey Jr playing dr doom is a great move by marvel. The aura gonna be insane to watch."

And a third wrote: "Honestly I didn't exactly like the casting but a few moments later after letting it soak in I realized I really love this casting and can not wait to see Downey as Doom plus HES FINALLY BACK IN THE MCU!!!!! I know it hasn't been terribly long but I miss him."

While there have been no further details on whether Downey's Doom will somehow connect to his Tony Stark, some were worried what the casting means for the villainous character.

One noted: "I… I dont know about this… Doctor Doom is my FAVORITE Marvel Villain… of like… ALL TIME… RDJ IS Iron Man, I cannot see him as anyone else other than Tony Stark… He is a great actor, but not gonna lie, would have preferred someone else in the role…"

Another shared: "Downey as doom I get as a decision from the studio, I’m worried they are gonna miss a lot of Dooms backstory if he is just slotted in for Kang. This character is complex and cool and evil and a badass and I hope to god they do him justice."

Others were a lot more pessimistic, suggesting that it would have been a good opportunity to bring another actor into the MCU.

One fan wrote: "Pretty disappointing. I love Downey but I’d much prefer a lesser known actor for Doom. I’m sure it’ll be good in the end but right now just a bummer and feels more like Disney desperately trying to ignite what once was instead of an inspired casting."

And then there was Thunderbolts* star Florence Pugh, who plays Yelena Belova in the MCU. When shown the moment Downey unmasked himself on stage by Variety, her jaw dropped as she added: "I didn't see this – I bet it went insane in there!"

Avengers: Doomsday and Avengers: Secret Wars will release in May 2026 and May 2027 respectively.

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