currently playing through all of mirror moon translated works. Gonna post all of the quotes here.
Akiha: I don't think Nii-san will die even if you killed him
Shirou: People die when they're killed(giving back Avalon to Saber)
Tohsaka: Look Emiya-kun. People normally die when they are killed. Your wound should be fatal, you know?
Kotomine: That is exactly right, Emiya Shirou. It is the law of nature for people to die from wounds. But you cannot kill what has not yet come into existence.
HF (good end)
Tohsaka: He can go get surgery at hospitals, drink cold medicines, and die when he's killed.