WARNING: The following contains spoilers for What If...? Season 1, Episode 4, "What If... Doctor Strange Lost His Heart Instead of His Hands?," streaming now on Disney+.

One of the main purposes of the What If...? comics was to show the consequences of the heroes losing. After Hank Pym's grief fueled murder spree of the Avengers led to a war with Asgard, this week's episode of the show raised the stakes. The darkest episode of What If...? so far ended with the death of an entire universe, showing the severe consequences of a change in the inciting incident of Doctor Strange's origin story. In the process, it showed how much the alternate realities of the Marvel Cinematic Universe can diverge from the films they're based on.

In the reality shown in What If...?, Doctor Strange pursues the mystic arts as a result of losing his love, Doctor Christine Palmer, who died in the car wreck that cost Strange the use of his hands in the mainstream MCU. Strange goes through his mystical training fueled by grief and eventually reaches a point where he feels he has gained the power to prevent her death.

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After defeating Dormammu and gaining custody of the Eye of Agamotto, Strange uses the Time Stone to travel back to the night where Christine died. After Strange fails to save her life multiple times, The Ancient One appears to offer him some guidance -- telling him that Christine's death can't be averted. It's an Absolute Point in time. If Christine doesn't die, Strange never fulfills his destiny of becoming the Sorcerer Supreme. When Strange argues, The Ancient One replies that he's risking the entire universe.

Strange ignores her warning that the path he's on only leads to darkness and the end of their reality. Her words, however, prove prophetic. Strange finds the power he seeks by absorbing multiple otherworldly beings before overwhelming a version of himself that accepted Christine's death. A demonic Strange saves Christine's life, at the cost of reality itself collapsing around them. Strange has to watch her die again before the episode fades to black.

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Beyond being darker than any previous MCU storyline, including The Snap, what stands out about this episode of What If...? is how much it deviates from the main timeline. While it can be considered an example of the Women in Refrigerators trope, the episode gives Christine a prominence she didn't have in Doctor Strange.

Christine was always an important character to Doctor Strange. She was the only person who stood by him after his accident, at least until he pushed her away. She wound up saving his life after his battle with Kacelius' Zealots. After she operated on The Ancient One they reconciled, sharing a kiss before Strange returned to his new life. That moment encapsulated how much  Strange had grown as a person. Despite her importance, however, Christine didn't get much screen time in his debut film. One of the criticisms of Doctor Strange was that it relegated her to the sidelines. What If...? changes that by making her a pivotal figure, not just in Strange's life but the universe itself.

This opens up a lot of possibilities for Marvel's Multiverse, as it proves details from the MCU can be changed significantly, giving characters a larger role than they previously had. This means supporting characters like Happy Hogan or Betty Ross could become pivotal characters in different corners of the multiverse.

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It also establishes not just that the key points are different in every universe, but that there are apocalyptic stakes for trying to alter those key points in the timeline. This is something that could become an issue beyond this episode, with time traveler Kang set to be the MCU's next big bad. If a desire to change the past corrupted Doctor Strange into dooming a universe, it's terrifying to think of the havoc a motivated Kang could wreak. Even if Kang doesn't get involved, trying to stop similar attempts at undoing Absolute Points could be what brings the Multiverse Avengers together, to stop what happened to Strange Supreme's universe from happening again.

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