death acceptance sans.in his world,he had the scarf that normally belongs to his brother.then the genocide was about as normal as they get,until after his death.when the world reset,he came back as this weird ghost thing,instead of his normal form,and he somehow was given the ability to travel across worlds.so,after the final defeat of chara,and frisk back in control,he said his goodbye's,and started going from universe to universe,seeing what the multiverse has to offer.