Warning: This article contains spoilers for What If...? episode 6.

The Marvel Cinematic Universe delivered a touching tribute to Robert Downey Jr.'s Iron Man in Avengers: Endgame, but Marvel's What If...? completely erased it. What If...? episode 6 changes the events of 2008's Iron Man, the MCU film that started it all. In the original movie, the Ten Rings organization kidnaps Tony Stark, and the ordeal inspires him to build the first Iron Man suit. In the What If...? version, Erik Killmonger (Michael B. Jordan) saves Tony Stark (voiced by Mick Wingert in the episode) from the Ten Rings. He becomes close with Stark and secretly manipulates Stark Industries from the inside, getting Stark to build automated killer drones and murdering Stark, James Rhodes (Don Cheadle), and T'Challa (Chadwick Boseman) in the process. He also manipulates the Wakandans and essentially steals the title of Black Panther.

In Endgame, Iron Man received a touching tribute following his death. During his MCU journey, Downey Jr.'s Stark went from genius, billionaire, playboy to a person who sacrificed everything for the good of others. And Iron Man's funeral recognizes that. In a touching scene from Endgame, Stark's miniature arc reactor, which reads, "Proof That Tony Stark Has A Heart," is set adrift on a lake. His loved ones, friends, and colleagues, including Tom Holland's Spider-Man, Jon Favreau's Happy Hogan, and Gwyneth Paltrow's Pepper Potts, look on as it floats away. It's a touching moment of reflection on the character who kicked off the first decade of the MCU.

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What If...? undermines Stark's tribute. In the episode, Killmonger enacts his plan to make Stark build and fund his killer drones, but the early tests for the weapons are going awry. The drones need a new power source, and Stark contemplates the problem. "Hey, if we could miniaturize and arc reactor," he says before dismissing the notion. "No, that's a dumb idea," he adds. Instead, the pair settle on Vibranium as a new energy source, and in doing so, the MCU brushes off a decade of Iron Man's character development.

Tony Stark shows arc reactor to Obadiah Stane in Iron Man

Marvel's joke is perhaps more flippant than it realizes. As Obadiah Stane (Jeff Bridges) says in Iron Man, Tony Stark built the reactor in a cave with a "box of scraps." The ordeal in the cave turned Stark from a selfish, heartless weapons dealer into a hero who eventually paid the ultimate sacrifice for the ones he loved. By dismissing the arc reactor as a "dumb idea," Marvel ignores the importance the studio itself put on the item. The arc reactor represents not only Stark's heart but also the heart of the MCU. And What If...? just dismissed it as stupid.

While the joke may have slightly missed the mark, it also emphasizes the point of the episode. In What If...? episode 6, Killmonger prevents Stark from being kidnapped. Therefore, Killmonger prevents Stark from developing his MCU heart. The Stark in the episode is pompous, arrogant, and an egomaniac. While the character usually has some of those traits, this Stark takes it to the next level. By brushing off the arc reactor (and essentially the tribute in Avengers: Endgame), Marvel shows how this Stark doesn't have a heart. Unfortunately, it may also be saying that the episode doesn't have one either.

More: The MCU Explains Why Tony Stark Can Never Be Revived

Marvel's What If...? releases new episodes Wednesdays on Disney+.

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