Undertale Last Breath

Undertale Last Breath (aka. Undertale Final Breath) is an AU fangame where after 30 genocide routes Frisk reached the 31st genocide, Frisk found a strange door, and found a strange figure who then left, sending Frisk unconscious. The strange figure informed Sans the skeleton of the past genocide routes, agitating sans to the point that he swears to kill the human, no matter the cost.