Talk:Genocide Route/@comment-32789293-20170806184053/@comment-26205543-20170917070250

Hopefully in a month and a half, someone found you an answer, but because I couldn't seem to get it anywhere on the Internet, maybe you couldn't either.

That being said, yes. My assumption is that when you've finished your portion of the Sans fight (the end of your work being pushing the Fight button for the last time), Chara takes over the killings entirely and uses a weapon of her own.

I played through the entire Sans fight using the Empty Gun because I myself needed an answer to this question (and also, come on, the Real Knife stats mean nothing when everything from the Stick up would one-shot him just the same), and when I got to the end and actually hit him, he was slashed at twice rather than shot.

Asgore was also slashed, and Flowey was cut down, all of which while I was holding the Empty Gun. I even left the Knife in the box just to be safe.

Side Note: It would seem the game is programmed in a way that predicts players who get the Real Knife will automatically prefer and equip it over other items, as Sans mid-fight still says "you, uh, really like swinging that thing around, huh?"