Lore

Basic Stuff:

So Sans Is like Dusttale and remembers the genocides that frisk dose and he basically loses his mind and decided to defeat frisk by in his words, (playing there game) and by that i mean killing everything on sight.

there isn't really and different but he doesn't care if you spare or kill everyone the ending will be the same. Also unlike regular Dusttale Chara doesn't have anything to do with this as she stop helping frisk after the 3rd Geno route.

Ruins:

Nothing really changes in the ruins but the only thing that changes is that Flowey helps you as he want this to stop too.

also after the Toriel encounter Sans BEATS THEM UP With his Pure Hands, But after that sans leaves Flowey Heals them up And Frisk truly realise what they have done so now they chill out with killing people.

Snowdin:

So Nothing also changes to the Orignal SP! Dusttale Snowdin As Sans Kills Everyone in Snowdin, So Flowey convinces Frisk to kill a hand full of people in Snowdin as there LV is 6 Exiting Snowdin.

Also Sans don't actually kill papyrus as there head didn't turn into dust so Flowey convince Frisk to end there suffering (Its a sad moment).

Waterfall:

So In Waterfall Frisk is still LV 6 and stops killing as they cant take it anymore so Flowey just helps them getting through Waterfall But then Sans encounters Frisk and Flowey Dies from holding off sans (Also a sad death as Flowey was the only one that made Frisk a bit more happy but now without them there allowed)

Hotland:

Nothing changes but Frisk dose kill Mettaton Neo to get up to LV 8 and Sans kills everyone else even Alphys So he has LV 14, He also kills Asgore as frisk walks though new home alone and after that the rest is history as now frisk must stop Him

Bonus Stuff:

Sans Misgenders Frisk a lot when talking to them.

Sans doesn't think he a god unlike what most people think but he dose bring up religious stuff that's in the bible.

Frisk in In Snowdin to Hotland talks shy a quietly to everyone

Also before Necroptosis Fight Sans dose just give up knowing that he wont win so he is making the fight more of a mental fight (Unless your the player then its both)

So that's it if you have any questions just comment on here

#Spdusttale