not to be serious about epic divorce man but like. the asgore fight is more or less the payoff of the advertised theme of undertale - “you don’t have to kill anyone”, and he does the most to challenge this theme, not just to the player but on a personal level, since the running motif of undertale’s monsters is that they don’t want to kill you either, but they have to or less they will never be free.

the scene beforehand, where small shock plays, is given additional context on replays and knowing how chara, flowey, asriel, and frisk all relate to each other - asgore is looking at someone who looks identical and acts identically to his child who, from his perspective, died of an illness that he could not prevent, and he has to kill them again

it is as equally “you cannot spare me” as it is “i cannot spare you”, which when juxtaposed against how asgore never uses attacks that are aimed at the player directly, creates the mood that is “neither of us want to be here but we have to be for there to be a future at all so someone needs to fucking die already” and its really fucking good