Ironheart ending explained: What does that game-changing cameo mean?

After weeks of speculation, Ironheart confirmed fan theories by revealing that Mephisto, played masterfully by Sacha Baron Cohen, had been pulling the strings from the start, and influencing Parker to achieve his own mysterious goals.

It was a grand finale, which, frankly, left viewers with more questions than answers, as Ironheart remained steadfast in its exploration of grief, above all else.

Heartbreakingly, episode 6 was all about the lengths that Riri was willing to go to get the AI version of Natalie (Lyric Ross) back, but after taking down Parker, and quite literally making a deal with the devil, a misguided Riri has plunged the MCU into a world of chaos.

Here, we break down that game-changing finale and explain why Mephisto's cameo is so cataclysmic...

Who is Mephisto? And what does his cameo mean for the MCU?

Episode 6 began by unravelling a key mystery. Opening with a flashback, fans learned that it was during a robbery with his late cousin John (Manny Montana) that Parker first encountered Mephisto.

After he and John had split up to avoid the police, Parker had fled into a tunnel, where a cloaked figure offered to help him escape. Desperate to get away, Parker agreed and stepped through a door into a diner, where he sat down with the extra-dimensional demon.

Tempted by Mephisto's offer to give him the tools with which he could achieve his deepest desires, Parker agreed to team up with the magic wielder. Determined to become so "stupid, disgusting, greasy rich" that he'd have more money than the father who abandoned him, Parker agreed without knowing Mephisto's real identity or his dark motives.

Once they'd struck a deal, Mephisto left Parker with the hood and promised to stay in touch, giving him the means to assemble a crew and start robbing the companies that his father, Arthur (Paul Calderón), had controlling interests in.

So, who exactly is Mephisto? As fans of Marvel Comics well know, the character is also referred to as the Monarch of Evil. Recognised as one of the greatest manipulators, he often strikes bargains with human beings for his own gain, while drawing power from their souls.

In the comics, Mephisto has been known to target the likes of Peter Parker/Spider-Man and Norrin Radd/Silver Surfer, among others. While it's unknown how Sacha Baron Cohen's version will specifically impact the MCU, Dominique Thorne has suggested that he'll pop up again.

"My gut is telling me that that is not the last we have seen of him, and I don't think that is the last that we've seen of him in connection with Parker, and obviously, clearly not with Riri," she told Deadline.

"I think Mephisto is probably in for a bit more of a headache than he bargained for with Miss Riri Williams. I think regardless of what Mephisto thinks is going to happen, Riri most certainly has other plans in mind."

What happened to RiRi in the Ironheart finale?

As the episode shifts from the past to the present, we find Riri desperate to recover the AI version of Natalie, after Zelma's (Regan Aliyah) magic resulted in her deletion. While Riri was given a second chance by Joe – AKA Zeke Stane (Alden Ehrenreich) – who lied to Parker by pretending he'd killed her, Riri risks it all and goes after the hood, convinced that its powers will help bring Natalie back.

As she arrives to confront Parker, Riri is met by Joe, who, as a result of his bionic enhancements, has been programmed to protect Parker at all costs. Forced to fight her old friend, Riri manages to get the upper hand and reprograms Joe, giving him back his freedom.

While Joe is somewhat grateful, he tells Riri that he has a lot of anger left in him and that they still have unfinished business.

As she heads upstairs, Riri fights Parker in his apartment, glimpsing how much the hood has corrupted his mind and body. When she activates the emergency protocol in her suit, Parker thinks he's finally won, but as he shoots Riri, he realises that the version in front of him is a hologram. At that exact moment, Riri emerges and takes him by surprise, claiming the hood for herself and leaving a crying Parker in pain.

Just as she's leaving, Riri encounters Mephisto downstairs. After mistaking him for Dormammu, the villain in Doctor Strange, he reveals his true identity and strikes a deal with Riri, thus allowing her to replace Parker.

In the final moments of the episode, there's a small time jump, and we see Riri continuing to work on her suit with both technology and magic. When Natalie suddenly appears, a delighted Riri asks her to run diagnostics, before realising that the Natalie in front of her is actually real, and that Mephisto has brought her back from the dead.

As Riri hugs her best friend, the camera zooms in on her arm, which, just like Parker's, has begun to be corrupted with dark veins.

What happened in the post-credits scene?

The post-credits scene brought us back to Parker, who is utterly lost without his hood. Tracking down Zelma, he asks her for some "heavy-duty magic" and "supreme-like help".

As Zelma contemplates his offer, the scene fades to black.

Could this be the start of a new partnership? Looks like we'll have to wait and find out.

Marvel's Ironheart is streaming now on Disney+.

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