On Friday, June 27, 2025, Marvel probably teased Mephisto's arrival in Ironheart through a post on its Threads account. However, it must be noted that as of now, we don't know if the hooded figure seen in the picture is Mephisto or just Parker Robbins. It must be noted that Mephisto's possible involvement is the thing that keeps Ironheart in cultural conversation, and Marvel will not spoil something this important.
It is important to remember that Mephisto's involvement in the Marvel Cinematic Universe was speculated by fans ever since WandaVision began streaming in 2021. While that series did not feature Mephisto in any way, speculations of the devil's involvement gained steam when Agatha All Along name-dropped him.
Furthermore, an October 2022 Deadline report revealed that Sacha Baron Cohen was cast in the MCU in an undisclosed role in Ironheart, which hasn't been officially revealed yet. The same report also mentioned Mephisto as a possibility, adding fuel to the fire. Now, it looks like Marvel may have joined the fray to hype up the devil's appearance, or troll the fans.
The latest Ironheart tease explained:

The picture above was posted by Marvel Studios' social media team on its Threads account to hype up the next three episodes of Ironheart. In the image before, a hand is holding a hooded figure at gunpoint. If you analyze it, the face of the hooded figure is darkened. It is possible that this particular moment was filmed like this, or Marvel intentionally held back the identity, to encourage people to watch the series coming Tuesday.
Why would Mephisto be involved in Ironheart?
Mephisto's possible involvement is tied to the mystical hood that Parker Robbins is using in the series. The hood helps Parker in pulling off the heists as it helps him turn invisible by holding his breath. In the comics, Parker Robbins steals the hood from Dormammu (the same Dormammu seen in 2016's Doctor Strange). However, several fan theories state that the MCU might have changed the ownership of the hood to Mephisto.
Parker might have summoned Mephisto to get a powerful magical artifact to help him strip his father, Arthur Robbins, of his power and influence. The devil hands Parker his hood in exchange for his soul. We see scars forming on Parker's body, indicating that his soul is getting corrupted. However, from Parker's perspective, he may feel that the price is worth bringing down his father.
We know that Arthur is the CEO of a company called Artworks, which invests in several companies in Chicago. As of now, everyone that Parker has targeted seems to be his father's business partners. With every use, scars seem to spread on Parker's body, hurting him, but he doesn't seem bothered. This might be Parker's ultimate downfall, making him one of the MCU's tragic characters.
"Set after the events of “Black Panther: Wakanda Forever”, Marvel Television’s “Ironheart” pits technology against magic when Riri Williams (Dominique Thorne)—a young, genius inventor determined to make her mark on the world—returns to her hometown of Chicago. Her unique take on building iron suits is brilliant, but in pursuit of her ambitions, she finds herself wrapped up with the mysterious yet charming Parker Robbins aka “The Hood” (Anthony Ramos)."
Want to find out the identity of the hooded figure by catching the Ironheart finale on July 1, 2025.