Spoilers ahead; you have been warned!
Christopher Nolan has revealed that he was not initially happy with Man of Steel’s bloody ending. Nolan, who produced the movie alongside Zack Snyder, was not on board with the decision to have Henry Cavill’s Superman kill General Zod (played by Michael Shannon).
In an interview with Empire Snyder broke it down for us: "In the original version of the script, Zod just got zapped into the Phantom Zone. But [writer] David [S. Goyer], Chris, and I had long talks about it, and I said that I really feel like we should kill Zod, and that Superman should kill him.”
"The ‘Why?’ of it for me was that if it was truly an origin story, his aversion to killing is unexplained. I wanted to create a scenario where Superman, either he’s going to see [Metropolis’s citizens] chopped in half, or he’s gotta do what he’s gotta do."
Goyer later explained that had always liked the idea, but that Nolan took some serious convincing. Nolan’s original opinion on it was: “There’s no way you can do this.”
Goyer then stated: “I came up with the idea of the heat vision and these people about to die. I wrote the scene, gave it to Chris, and he said, ‘Okay, you’ve convinced me.’”
Superman murdering General Zod has been a popular topic of conversation between movie-goers, as well as Superman purists. One lifelong Superman fan told me that there was no other option, and although it was certainly a different outcome than he expected, he was really happy with it: “This Superman was much more realistic than any of the others. Considering the history he had with Zod, I don’t know what else could have been done. Superman had to kill him, no question about it.”