Warning: This article contains spoilers for What If...? episode 7.

The Marvel Cinematic Universe turned Thor into an only child in Marvel's What If...?, and it also subtly changed its silliest mistake with the God of Thunder. What If...? episode 7 changes Thor's (Chris Hemsworth) backstory, making him an only child and letting Loki (Tom Hiddleston) grow up on Jotunheim. Without his brother around, Thor becomes easily bored and turns into Party Thor. When his mother, Frigga (voiced by Josette Eales), is away from Asgard, Thor travels to Earth and throws the biggest party in the history of the MCU. Unfortunately, his parties tend to get out of control and could even be world-ending. This puts him on the wrong side of Captain Marvel (voiced by Alexandra Daniels), and eventually, Jane Foster (Natalie Portman) tells Frigga about Thor's dangerous party. With his mother on the way, the God of Thunder abruptly ends the celebration before there's any lasting damage.

Other than being an only child, Thor doesn't change much in the episode. Like in 2011's Thor, the character is still arrogant and headstrong. In Thor, he defies Odin's (Anthony Hopkins) orders to leave the Frost Giants alone, attacking the creatures on Jotunheim and eventually getting banished to Earth. Likewise, he defies Frigga's rules in What If...?, traveling to Earth to party after his mother told him to study on Asgard. In his MCU film, Thor eventually learns he was wrong, and he comes to the same conclusion in What If...?.

Related: Why The Watcher Was Shocked At [SPOILER]'s MCU Return

Though Thor generally stays the same, the episode includes one small change. In 2011's Thor, Hemsworth's character has blonde eyebrows, which match his hair. The actor had to dye his eyebrows for the movie, which created a distracting look and could make his brows appear invisible at times. Marvel boss Kevin Feige later admitted Thor's eyebrows were a mistake, saying it was something he'd change in the MCU. In later films, Hemsworth doesn't have blonde eyebrows, and What If...? doesn't make his eyebrows match his hair either.

Thor and Ayesha in What If

The eyebrow change is a welcome MCU update. As Feige admitted, the God of Thunder's eyebrows were a travesty in the first Thor movie. Blonde eyebrows don't stand out like darker eyebrows, so in some shots in Thor, it could seem like the God of Thunder didn't have any brows at all. Though the What If...? episode appears to take place around the same time in the timeline as Thor, it correctly goes along with the later MCU films, giving Thor darker eyebrows instead of the yellow highlighter-looking marks from his first film.

At this point, Marvel uses What If...? to retcon whatever it wants. Sure, being an only child wouldn't necessarily change Thor's eyebrows, but that doesn't matter to the studio. Thus far, Marvel has added several changes to its MCU stories that don't get explanations. The studio retconned time travel rules and even Black Widow's (Scarlett Johansson) background, showing Nick Fury (Samuel L. Jackson) played a more significant role in her defection than previously thought. The fact that the Multiverse has endless possibilities is the only excuse for the retcons. The changes may not all make sense, but at least Thor finally has eyebrows worthy of the God of Thunder.

More: The MCU Just Retconned Black Widow's Defection Story Again

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

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