Spoilers for Infinity War can be found throughout this story, if you haven't yet caught the flick.
You'd think playing a baddie like Thanos with seemingly infinite reserves of strength and wild, universe-changing goals would be a lot of fun. However, it's not all fun and games in the Marvel Cinematic Universe. Josh Brolin, who got to bring Thanos to life on the big screen, said he focused on creating a "sympathetic version" of the villainous character in a recent interview. Regardless, there was one scene in Avengers: Infinity War that was more difficult to shoot. Brolin didn't really enjoy shooting the scene where he was forced to choke out and kill off Asgard's adopted son Loki. He said:
He had been with that character for so long. And he's so lauded for doing it. Tom was so vulnerable at that moment. So, choking him out wasn't the most fun thing I have ever done.
If you've seen Avengers: Infinity War, you already know that Loki finally takes his last breath early on in the movie. His trickster personality finally gets the better of him when he tries double-crossing Thanos, making it seem as if he will be an asset to Thanos and his minions while forsaking his brother with a clever speech. He's really sticking with his brother and his people, though, as he also has a weapon and tries to use it on Thanos, but is overpowered in the process. The next startling moments in the movie feature Josh Brolin's character choking Loki out, leading to his ultimate death. It's a death that is likely to stick, even if the dusted people don't, and Tom Hiddleston has previously revealed he knew it was coming for quite some time, even while he was working on Thor: Ragnarok.
Speaking to USA Today, Brolin admitted that while he was fine having his character choke out Loki, it wasn't the easiest scene, mostly because of Tom Hiddleston's performance and his ability to jump right into the moment and emote. Hiddleston's been playing the character for nearly as long as the Marvel Cinematic Universe has existed, appearing first in Thor and becoming a lively and popular villain with a heart of gold in the movies. As such, being the sordid bad guy to take that kind of talent out was not the most fun that Josh Brolin had on set.
Still, not all of the moments in the movie were that tough to get through. Brolin also revealed that he had some great fun with some of the other characters, too, especially during the showdown between The Hulk and Thanos early on in the movie when Thanos takes a cheap shot at Bruce Banner's alter ego. He noted:
I love that Thanos uses a knee. That was great.
All in all, Brolin enjoyed playing Thanos, and also mentioned he even enjoys people hating on the character online, so he takes a lot of great joy out of playing the big baddie villain. Let's just hope that he doesn't have to take out too many great heroes during the events of Avengers 4. On that note, though, I'm not holding my breath.