"Snyder weighed in with the idea that Superman killing Zod is actually key to him developing as a hero. “If it’s truly an origin story, his aversion to killing is unexplained,” Snyder said. “I felt like, if we could find a way of making it impossible for him - Kobayashi Maru, totally no way out - I felt like that could also make you go, ‘This is the why of him never killing again.’ He’s basically obliterated his entire people and his culture, and he is responsible for it, and he’s just, like, ‘How could I ever kill again?’” The idea of a morally ambiguous and unpredictable Superman seemed to resonate with the director. “If there were more adventures for our Superman to go on, you’re given this thing where, you don’t know 100 percent what he’s going to do. When you put in stone the concept that he won’t kill, and it’s totally in stone, it really erases an option in the viewer’s mind…you’ll always have in the back of your mind, ‘How far can you push him?’ If he sees Lois get hurt, or his mother get killed, you just made a really mad Superman that we know is capable of some really horrible stuff, if he wants to be. That’s the thing that’s cool about him, in some ways. The idea that he has the frailties of a human emotionally. But you don’t want to get that guy mad,” he said."