Prologue

🚫NOT SHIPP, by my colors🚫

Nightmare is the greatest villain in the multiverse, his name runs through the mouths of those who fear him and spreads like a virus. Feared by all, Dream's brother is trying to create a world of horror where positivity is impossible.

For that he has his subordinates, Murder Sans (or Dust), a Sans who came from a universe where he committed genocide to stop the player, and it cost him his sanity.
Horror Sans, coming from a world of hunger where it's devour or be devoured, abandoned by Frisk and with the death of their king, the monsters found themselves in an abyss of negativity and hunger.
Fell Sans, his AU is one of the best known among all the others, the Love addicted Sans who came from Underfell, a universe where all characters switch routes, so the underground is genocidal, his sadistic and apathetic personality attracted Nightmare to the universe where it's kill or be killed.
And the boss's favorite, Killer Sans, the assassin came from a universe where Chara controlled Frisk to do several genocides, and in an attempt to stop humans, Sans absorbed the player's soul, merging with Chara and losing his sanity, becoming a Genocide. as she.

Perfect for Nightmare to wreak havoc, controlled by his bloodlust and Nightmare knows how to please them in exchange for their loyalty.

We know we have Ink and Dream to oppose the villains, but what if Nightmare killed his brother, what would be in store for the Multiverse without the guardian of positivity? What if Ink decided to do nothing to see what would happen since he was bored? And where is Error in this conflict?

{PS- Cross here is not part of the Bad Guys because he is stuck in the AU with nothing on him, and I don't see Error as a Bad Guy, since he hates everything and everyone and as one of the strongest beings in the Multiverse, he will never obey the Nightmare.}