Actors practice and rehearse their lines in order to make the scene interesting and authentic. Especially with movies that involve some action, rigorous training and rehearsals are done in order to make certain actions as real as possible.
This is what the Marvel Cinematic is mostly composed of; fighting scenes, stunts, and lots of action. And knowing this, we could say that the actors go through a process to make the fight seem that it's actually happening. They have to make it look like they are in a lot of pain.
MCU's Loki played by Tom Hiddleston and Thor played by Chris Hemsworth might have disregarded this practice, which was revealed by Hiddleston himself.
Although in a film like the Avengers, it would be "all about angles." Showing the best possible angle to mimic a real fight scene, and that several takes are made to capture the "perfect moment."
Of course, Thor and Loki can't afford to not get into a fight. A particular scene in the first Avengers movie was where Hemsworth is supposed to hit Loki.
Hiddleston recalled this particular moment in a recent appearance on The Late Show with Stephen Colbert, as he shares about the time Hemsworth actually punched him in the face.
Hiddleston was wearing the heavy horns, as per his character. He mentioned that those weigh about thirty pounds. It was hard for him to mimic being hurt with all the weight his head is carrying; and that he "couldn't sell the smack". So, in an effort to make the punch look real, Hiddleston made a request to Hemsworth. "Just hit me in the face," Tom says to Chris.
The actor then joked about how he "went down like a stone," seeing as Chris is a very strong guy. He admits that if he were to do that on Broadway, he would not survive getting hit by the God of Thunder in the face day by day.
Hiddleston is currently making his Broadway debut on the show, Betrayal, in New York City.
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