Warning! This article contains spoilers for Ironheart season 1.

Ironheart premiered a villain in the Marvel Cinematic Universe (MCU) who had long been rumored to appear in multiple earlier projects. While the cast of the MCU has constantly been expanding since it began in 2008, the catalog of characters from the Marvel Comics isn’t close to being exhausted.

However, there are a handful of iconic characters that repeatedly come up in discussion to bring to the MCU. And over the last four years, one specific Marvel villain has been theorized to appear more than most. But thanks to Ironheart, he has finally made his on-screen debut, albeit a few years later than anticipated.

Mephisto Is The Main Villain Of Ironheart

Mephisto Made His MCU Debut After Years Of Anticipation

While the first five episodes of Ironheart position Parker Robbins as a primary antagonist for the series, there is a bigger presence pulling the strings. Mephisto, Marvel’s own version of the literal devil, appeared in Ironheart, season 1, episode 6, and with his arrival, the power dynamics have once again shifted in the MCU.

Mephisto is a being of spectacular power, and, despite teasing Dormammu as being the enтιтy behind Parker’s hood, as it is in the comics, Mephisto has revealed that it was his doing. But Parker was just a means to an end for Mephisto, and as of the end of season 1, Mephisto has recruited Riri Williams by his side, which will undoubtedly cause chaos in the near future.

Why The MCU Waited So Long For Its Mephisto Debut

The MCU Had To Be Careful About How They Approached Incredibly Powerful Characters

While the comics have dozens of characters whose power levels are through the ceiling, the MCU has to be more careful and deliberate with the balance of power. If too many powerful beings are introduced too quickly, other characters and stories may become irrelevant.

Likewise, these characters would mᴀssively overshadow others, and lead to frustration. But the MCU has been careful, and slowly built up the number of extremely powerful beings, ensuring that the stories can be compelling, and continue to have high stakes.

Alongside Mephisto’s arrival, characters like Sentry, Franklin Richards, and the Mutants are all set to join the MCU and ensure the scales don’t tip too far for the villains.

Why Ironheart Initially Teases Another Villain Being Its Main Antagonist Instead Of Mephisto

Dormammu Was Being Namedropped In Ironheart Before Mephisto’s Big Reveal

As mentioned above, Dormammu was initially hinted at being behind Parker Robbins’ powers. In the comics, this is how the story plays out, and both an enchanted hood and a pair of boots give Parker the power he needs to become the villain, The Hood. However, the MCU is taking a different approach.

Dormammu still appears to have a presence in the MCU, but after his conflict with Stephen Strange in Doctor Strange, he has yet to cause more trouble on Earth-616. Meanwhile, Mephisto was teased in WandaVision, Loki season 2, Agatha All Along, and even Doctor Strange in the Multiverse of Madness.

Evidently, it was time to finally bring in the lord of the Hell dimension into the MCU, and it could play a part in Doctor Doom’s upcoming MCU story. However, where and why he pops up next remains a mystery until then, but at least Ironheart set the stage for Mephisto.