Mephisto Is Finally in the MCU: Ironheart's Ending Explained and the Supernatural Era It Sets Up

Marvel finally did it: Mephisto is in the MCU, played by Sacha Baron Cohen, and he arrives in the finale of Ironheart. This is my favorite thing ever in the history of forever, and when this piece was written in July 2025, Marvel Studios did have plans to include Mephisto in future MCU projects.

In fact, he says a really big line to Parker in this finale that could heavily imply what comes next for him, and I think his story in the MCU is going to be a lot bigger than people realize. I will get to that line, and to where Marvel appeared to be heading with him, after breaking down how the episode ends.

Sacha Baron Cohen's Mephisto was worth the long wait

We have waited such a long time for this, going all the way back to the WandaVision days. Since then, Mephisto has been a legend, and nothing but memes. A lot of people gave me a hard time about all my Mephisto theories, which is great. I loved it all. It has been a journey, but he is finally here.

I think Sacha Baron Cohen was absolutely perfect, perfect casting for Mephisto. When he dropped his line saying his name in this episode, I got literal chills. I also loved how he made fun of Riri for thinking he was Dormammu, or really made fun of the fact that anybody would think he is Dormammu.

The flashback with Parker shows how Mephisto operates

The episode opens with a flashback to where Mephisto first met Parker. Parker is running away from the house of his father, the father who abandoned him, and security is chasing him. Just when it looks like Parker is about to be captured, a mysterious figure shows up offering to help, and he magically makes a door appear out of nowhere. Then we finally see that it is Sacha Baron Cohen.

We had heard for such a long time that he was going to be Mephisto in this series. But due to all of the trauma that WandaVision caused us, there was still a lot of doubt that Mephisto would actually be in it. Our hope finally paid off. The door he conjures leads to the place that would later be used as the Hood and his gang's hideout.

This is where we start to see how Mephisto works. He is cunning, sly and charming, and he speaks in your ear like the devil on your shoulder, because Mephisto is essentially the MCU's version of the devil.

Mephisto's comics history makes him a pretty big deal

Mephisto rules over his own dimension, which he does call hell, and in his realm he keeps very evil people, such as Adolf Hitler. He is also responsible for creating Ghost Rider. He was jealous of the worship that the fire demon Zarathos received, so, posing as Satan, Mephisto created Ghost Rider by bonding Zarathos to Johnny Blaze. He was also at the side of Thanos during the Infinity Gauntlet saga.

In the comics, he takes Cynthia von Doom, Doctor Doom's mother, to his hell dimension. That is how Doctor Doom originally gets his scars: he tries to build a device to communicate with his mother in the hell dimension, and it explodes and scars his face. Later on, Doom, with the help of Doctor Strange, goes to the hell dimension to try to defeat Mephisto and retrieve his mother. They never really succeed. Mephisto usually wins. So he is a pretty big deal in Marvel history, and he has finally debuted in the MCU.

The restaurant scene reveals Mephisto's true form and a shifting accent

Back in the flashback, Mephisto tells Parker he can basically give him anything he wants, or at least give him the tools and the power to get it. As they talk, he shows off his powers by silencing a family in the corner, then the whole restaurant. Then he says he could do it to the whole city, and that is the big line I will come back to. The whole time, we hear him whispering in Parker's ear, basically telling him, "Do it. Partner with me." That is essentially what happens later with Riri too.

Make no mistake, he is pure evil. He simply knows how to get what he wants, and in most cases you catch more flies with honey than with vinegar. We get a glimpse of his true form in a spoon, completely red and very demon looking, but rather than appearing like that, he appears in human form.

Notice how his accent switches. We are talking about a demon who has been around for a very long time, so I am assuming his accent changes a lot based on who he is talking to and the circumstance. I am glad it switched, because in my personal opinion that accent at the beginning did not seem to fit Mephisto.

Mephisto abandons Parker and turns his attention to Riri

When he appears to Parker again as Riri is making her way to him, we see his true colors. He says, "I said be careful how you speak to me," and we hear his demon voice come out. He tells Parker, "Well, how about I just replace you?" He does not actually care about Parker, or about anybody. He used Parker to get what he wanted, and now he is going to use Riri the same way.

He is sly about how he goes about it. He takes something he says people will not miss. The show does not say what it is, but if we go by the comics, it is their souls. Mephisto primarily seeks to enslave human souls in his hell dimension, so perhaps it is not something you will miss while you are alive, but definitely when you are dead and trapped in his realm.

Ultimately, Parker asks Mephisto for more help, and Mephisto essentially abandons him. He lets him keep the hood, but Riri defeats him using her suit combined with magic, takes the hood away, and starts walking off.

Mephisto's pitch to Riri reveals deals with the world's most powerful people

Mephisto is waiting for her in the restaurant, eating pizza. He gets her attention by magically forcing her out of her suit. She sits down and he starts to sweet talk her, calling her magnificent and intelligent, and describing her as someone who, through no fault of their own, always finds themselves at the short end of the stick. I mean, she had a full ride to MIT plus grant money, so I would not exactly call that the short end of the stick.

One important thing he says is that he has made a deal with every single person on the Forbes list of the 100 richest, plus 14 kings and three popes. Essentially, Mephisto is behind the powerful people of the world, which suggests he is the one manipulating how things go. He also mentions Ringo Starr of the Beatles, a joke based on unconfirmed rumors that his unique drumming style came from his grandmother performing exorcisms on him.

Riri still thinks he is Dormammu based on the previous episodes, but he laughs in her face. Apparently Dormammu is nothing to Mephisto, and Dormammu is massive, which means Mephisto is on another level. Then, very surprisingly, Riri makes a deal with him after he plants many images of someone in her mind. Eventually that person comes back, and we see on Riri's arm that she did indeed make a deal.

Riri's deal might be addressed in Avengers: Doomsday or after Secret Wars

I am not sure Marvel will address this with Riri the way it originally planned, because Ironheart was filmed more than three years before its release, and Marvel's plans for essentially everything have changed since then. As of July 2025, they might have addressed it in Avengers: Doomsday, with Wong or Doctor Strange doing a spell to get rid of Mephisto's influence over Riri, or they might have revisited it after Avengers: Secret Wars, because Mephisto looked set to stick around for a very long time.

Mephisto was rumoured to be the big bad of the supernatural side

Way back in 2019, Kevin Feige, the president of Marvel Studios, said there would be different sides of the MCU he wanted to explore: a grounded side, a cosmic side and a supernatural side. Those plans did not work out as expected, because right after 2019 came the pandemic in 2020, then the writers and actors strikes, and then Marvel moved away from Kang altogether and brought in Robert Downey Jr. as Doctor Doom.

Still, Marvel started on the supernatural side with projects like Werewolf by Night and Agatha All Along. It had planned on releasing Blade, which, as of July 2025, had been delayed for a long time and might never have been made. And more than three years before its release, it made Ironheart.

At that point, we knew that after Avengers: Secret Wars, the next phase was set to focus on three areas: the mutants, the cosmic side and the supernatural side, each with its own big bad. It sounded like Annihilus would be the big bad of the cosmic side at first, and we had been hearing for a while that Mephisto would be the big bad of the supernatural side. We even heard a long time ago that the villain of Blade would be influenced by Mephisto, and here, the villain of Ironheart was influenced by him.

That points to characters and teams like Ghost Rider and the Midnight Suns, and hopefully Blade eventually debuting with Mahershala Ali. Who knows whether Dane Whitman, the Black Knight, was still planned to be part of the group. The Eternals post credits scene had Blade appear to him because Marvel's original plans were for Blade to be something like the Nick Fury of the Midnight Suns, assembling a team to fight villains, including Mephisto. Even though Blade was not really in the equation anymore, at least for then, it did seem like that was still the plan.

The Cosmic Circus said it seemed like Marvel wanted a Damnation style storyline

There is one particular story we heard, granted a while ago, about Marvel's plans for Mephisto. It came from the Cosmic Circus, and it seemed like Marvel basically wanted to do a Doctor Strange: Damnation storyline. In that comics crossover, Mephisto takes over a large part of Las Vegas with his own hotel, Hotel Inferno, and affects heroes like Black Panther, Captain Marvel, Falcon, Hawkeye, Jane Foster and even Doctor Strange, turning them into Ghost Rider like creatures.

Wong then assembles the Midnight Suns, including Blade, Moon Knight, Elsa Bloodstone, Doctor Voodoo, Ghost Rider, Iron Fist, Scarlet Spider and Man-Thing, to go up against the possessed Avengers, and they eventually defeat Mephisto. It seems like we could be building to that story, or one very similar, where Mephisto starts to take over parts of the world. Based on his deals with the richest people, kings and popes, he already has a really big influence and is essentially building himself an empire.

The Mephisto scenes salvaged Ironheart for me

Marvel is building to Mephisto being a big bad, and I think that is awesome, because Sacha Baron Cohen was perfectly cast. To be honest, I did not enjoy the show that much. It is not for me. But the Mephisto part was insanely awesome, and those scenes really salvaged the show for me.

What did you think of Ironheart as a whole, and of Mephisto's introduction to the MCU?