In order to make characters and events feel like they fit in the real world, Marvel has taken the approach with their movies of trying to make them as grounded as possible. Of course, this is difficult to do when dealing with things like Norse gods or aliens from outer space, but for the most part (especially in the early phases of the MCU), Marvel has managed to ground the more fanciful elements of the comics in some sort of science, or at the very least a more logical explanation that would make sense within the confines of our world.
While this helps to place the MCU in the real world, it also takes away some of the inherent fun from the comics. They've recently leaned more into magic existing in the MCU rather than just trying to explain away magical events with «science», but it's a strange balance that they now have to strike between grounding the story and letting in more of those fun superhero elements to create an entertaining story. The MCU may have shot itself in the foot a bit when they decided to ground the stories as much as they did, because it's made the process of transitioning to magical elements a bit more jarring and less believable for some viewers.
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Magic was introduced into the MCU slowly, and was used very sparingly at first. Very few characters in the early phases actually had magical powers, and they either used technology or had some sort of genetic «mutation» or ability that was given to them in a scientific way. This tracked with all of their comic book counterparts, but with the exception of the Thor series, the MCU tended to stay away from magical characters because they wanted to establish realism. Once they had this basis,
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