Talk:Genocide Route/@comment-38573614-20190410062045/@comment-27537247-20190621191915

You only fight Sans if you go through with everything else. You can still halt a Genocide run after killing Papyrus; you can fail the kill count in Waterfall so you never initiate Undyne the Undying and spare Undyne afterwards. Or you can do the same in Hotland, an refrain from killing Muffet and Mettaton EX. It is only too late once you've fulfilled the kill count in Hotland, because there is no way to spare Mettaton NEO. Sans doesn't kill you because you killed Papyrus; he kills you because he knows he has no choice. He says himself: "I can't afford not to care anymore."