Centuries ago monsters and humans ruled over this world, constantly locked in a war with no end.
Both sides would eventually become tired of war, but neither felt they could surrender. Mostly to end this war, the monsters fled underground. Unfortunately, six treacherous humans used there life force to trap the monsters below ground, with no way to leave.
However, legend tells that one day a human child will fall to the Underground, and lead the captive monsters to freedom.
Pacitale is a Undertale AU that is basically the exact opposite of Underfell. The common philosophy is "Spare and be spared." Just like in Undertale, you have the option to kill or spare monsters. The only difference is that it is designed to be easier to spare than to kill because the monsters are ready to spare you at the beginning of the battle, but if you attack, all but a few will have to be convinced to spare you again.
Frisk- essentially the same as in a Pacifist run of undertale
Chara- "Hey Human, Let me show you how it works down here... I wanna help you" In this AU, Chara is essentially Flowey, and will launch her "Friendly Slashes" at you. She is the only character who wants to kill you, but someone saves you before she can.
Asriel- Once Chara hits you with a Friendly Slash, you will have 1 health left. Chara will begin to tell you that this is how she "greets everyone like this", But Asriel will walk up and interrupt her.
"Chara, sister... whats the rule?"
"But Asriel I really wanna..."
"Ugh, Spare and be Spared, fine, whatever."
Asriel will take you to the ruins and teach how things really work in Pacitale's underground.