Marvel fans have been losing sleep over a voice, and Robert Downey Jr. is officially the man behind it. Ever since VisionQuest ended with Doctor Doom declaring, “Scarlet Witch, awaken — your power will be mine,” because the voice was deeper than Downey Jr.'s, the post-credits scene had fueled endless theories, even one that said that Cillian Murphy is actually secretly playing Doctor Doom in Avengers: Doomsday.

Now, showrunner Terry Matalas has confirmed that Downey voiced the line himself, revealing that the dialogue was specifically designed for that moment.

Robert Downey Jr.'s Doctor Doom reveal in VisionQuest was no last-minute Easter egg; the voice was deliberately crafted to make that post-credits moment count. Showrunner Terry Matalas told Gold Derby, who wrote and directed the finale, has now confirmed that Downey himself delivered the ominous line, although Matalas was not personally behind the camera for that particular sequence.

"That’s Downey’s voice. I can’t talk too much about how it was constructed, because I don’t want to give away, but yes, that line was designed for this moment, specifically," he declared.

The decision to bring Elizabeth Olsen's Wanda Maximoff back as the finale's final surprise also served a larger purpose than simply giving fans another reason to speculate about Avengers: Doomsday. With WandaVision having introduced Marvel's Disney+ era in 2021, Matalas saw Scarlet Witch as the missing piece needed to bring this chapter full circle. The creative team had considered several approaches to her return before settling on the Doctor Doom message as the most promising way forward without taking the spotlight away from Vision.

"It was something we all knew that we had to have. She was the missing component of that finale, and we talked about a dozen different ways to bring her back," he told Gold Derby.

The finale consequently leaves Wanda's return as a direct thread leading into Avengers: Doomsday, scheduled to arrive in theatres on December 18, 2026. Rather than treating her resurrection as a standalone surprise, Marvel has positioned it as a significant piece of what comes next.

Is Cillian Murphy in 'Avengers: Doomsday'? Why Are Fans Convinced He Is Playing Victor von Doom?

With the slightest vocal twist sparking Cillian Murphy theories, Downey Jr. may be confirmed as Doctor Doom, but Marvel is still keeping fans guessing about the villain.

Robert Downey Jr. may have traded Iron Man’s armor for Doctor Doom’s mask, but Marvel is not exactly handing fans the keys to the castle. Kevin Feige has confirmed that Downey is playing Victor Von Doom, not a Tony Stark variant, drawing a clear line between the actor’s former hero and his formidable new villain. That settles one debate, though hardly the most interesting one.

There is considerably more to uncover about the man beneath the metal. Joe Russo and Downey have revealed that Doom is a grieving father driven by the loss of a child, with multiversal destruction offering his twisted route to rebuilding reality. Add a gothic magic-wielding presence, a heavily scarred face, and a willingness to sell his soul, and the picture becomes darker without becoming clearer. Marvel may have revealed its leading man, but as Avengers: Doomsday draws closer, Doctor Doom remains a mystery with excellent timing.

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Did you figure out Terry Matalas's reveal beforehand? Let us know in the comments!