Warning: The following contains major spoilers for the Disney+ miniseries Ironheart.

After the red herrings in WandaVision and Agatha All Along, the Marvel Cinematic Universe finally introduced Mephisto in the final moments of Ironheart. Mephisto — essentially the Devil in Marvel Comics lore — is played here by a smooth-talking, bearded Sacha Baron Cohen.

His introduction to the MCU has major implications for upcoming films like Avengers: Doomsday.

But the existence of Mephisto isn’t the biggest game-changer in the last five minutes of Ironheart. To understand the impact of those moments on Riri Williams (Dominique Thorne) and the MCU, there’s a lot that Watch With Us needs to unpack.

Who Is Mephisto?

Mephisto is inspired by Mephistopheles, the demon with whom Dr. Faust made a damned bargain in the famous German legend. Marvel’s Mephisto has the same penchant for making devilish deals with comic book characters, including Ghost Rider, the Scarlet Witch and Spider-Man, among others. Of course, these deals always come with some kind of horrible price.

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What Happened Between Mephisto and Riri?

After spending the season mourning the death of her stepfather and her best friend Natalie (Lyric Ross), Riri gave in to her darkest desires and struck a deal to bring Natalie back from the dead. The catch, according to Mephisto, is “nothing [she’d] miss” — a frustratingly vague cost that’s heavily implied to be her immortal soul.

What’s the Significance of This Choice?

Riri’s decision to go along with Mephisto is a huge narrative swing for the MCU, as it takes a divisive character and has her double down on her own worst impulses. Riri’s arc throughout the season was about learning to let people in and deal with her grief, but instead, she opted to find an out-of-the-box solution for the “problem” of Natalie’s absence. Thus, a character we were supposed to root for as she grew through her journey made an obviously wrong choice.

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Riri is not the first Marvel hero to go bad — Wanda Maximoff (Elizabeth Olsen) enslaved an entire town in WandaVision and went full mass murderer in Doctor Strange in the Multiverse of Madness. But Riri’s journey was presented very differently. WandaVision showed Wanda apologizing for her actions in Westview, which started as an accident. Multiverse of Madness implied that Wanda had been corrupted by the influence of the Darkhold, the powerful Book of the Damned.

Riri’s choice was entirely her own. And although she double-checked that none of her friends or family would be beholden to her deal with the devil, she went into it knowing the destruction that a partnership with Mephisto could cause — she’d already seen it in Parker Robbins, a.k.a. The Hood (Anthony Ramos).

Perhaps Riri’s arrogance made her believe she could outsmart Mephisto, or perhaps her grief was just so strong that she didn’t care what happened to her. But either way, in Ironheart we see a character who failed to live up to the lessons she’d learned throughout her arc.

Resurrection in the MCU

Riri’s choice to have Natalie resurrected by Mephisto also has major implications for the nature of death in the MCU. We’ve seen dead characters return in one form or another before, but it’s usually been an alternate version of them or a time variant — like Loki (Tom Hiddleston) in Loki or Gamora (Zoe Saldaña) in Guardians of the Galaxy Vol. 3. But this was just Natalie, back from the dead, seemingly exactly as she was right before she was killed.

Natalie’s resurrection marks the first time a character has been brought back to life right away in the mainstream MCU. (A few more exceptions include Phil Coulson in Agents of S.H.I.E.L.D. and Elektra in Daredevil, but their relationship to Marvel’s sacred timeline is somewhat murky.)

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The implications of Mephisto’s resurrection abilities are huge for beloved characters like Wanda Maximoff, Natasha Romanoff (Scarlett Johansson) or even Tony Stark — especially since we already know Robert Downey Jr. is returning to the MCU as Doctor Doom. Who else might make a deal with the devil to bring back these heroes?

‘Ironheart’ Is Changing the Game

While reception to Ironheart has been somewhat mixed — many fans suspect that haters have been review bombing because of the protagonist’s race and ethnicity, while critical responses have leaned more positive — there’s no doubt this series made big, bold moves for the MCU.

Here at Watch With Us, we’re definitely fans, and we’re excited to see how Riri’s dark decision will steer the larger narrative of the Marvel Cinematic Universe.

Watch Ironheart on Disney+.