Chapter 1: The Realization of Tragedy

It's been about 6 months since a neutral/pacifist ending. The town is peaceful, and everyone stayed in the Underground, except Papyrus. He wanted to see more humans and learn more about them. So he left before the events of Book 3. Sans was against the idea, but he let him go, trusting his brother, saying that if I finds out if anything happens to him, he'd come and find him. However during his time on the surface, Papyrus dies. This is the story of Sans came to the surface and how he knew about the Z-crew.

In the cold town of Snowdin, it was getting late. Frisk had been out from playing with Blake. Toriel was at home cooking dinner. Everyone in the town was relaxing. Fireplaces were lit, neighbors were enjoying each other's company, playing games, sleeping, watching TV, etc., except one.

Sans was sitting outside, on a bench facing a lake, face buried in his hands, crying. His life had been flipped on its head. Sorrow filled his heart and overwhelming sadness carried in his cries. He thought about the encounter with that flower, the one that had tried to manipulate his brother, Papyrus, and the encounter with the dark blue haired human.

'"Hello, smiley trashbag," said a bright yellow flower, "I see that Frisk hasn't reset yet. Life must be good for you." Sans looked down at the flower in disgust.

"...yeah, I guess so. I'm surprised you're not hiding away. Then again, you known me for too long." His white pinpricks in his sockets disappeared, leaving nothing but darkness.

"You are still so naïve, after all these years, thinking that everything is ok; that everyone...is ok."

"Toriel is cooking dinner right now. Frisk is with their friend, playing games. How is everything not ok?"

"Where's Papyrus, then?" Sans' eyes widened.

"He's on the surface. He... left here because he wanted to learn more about how humans live," he said. Flowey laughed sadistically.

"I feel the fear and sadness in your voice. It would be a shame if something happened to him and you couldn't stop it." Sans, knowing Flowey in the past, became angry.

"You know something I don't? Huh?!" His left eye blazed blue. Flowey just smiled, but scooted back. He dealt with Sans before, him being one of the only people he couldn't beat.

"You'll see...you'll find out." Then he went under the ground.

Sans had resumed walking, but the mood was different. It wasn't calm, but tense. Sans' intuition had always been very reliable, dealing with the past humans, judging them. But this time, his gut spoke uncertainty, something he hadn't felt since after Frisk beat Flowey. It was dark now, the clouds had covered the moon, darkening the land. Just then, Sans felt a presence in front of him. He felt this clouded energy all around him. He stopped and tensed up, knowing that he hadn't felt power this strong in Snowdin.

"Who's there?!" There was silence, except the breeze blowing and rustling the leaves. Then, he heard someone chuckle to the right of him.

"I had a feeling you'd be around here." Sans looked and saw a human step from behind a tree.

"Chara?" Sans thought, "No, this one is different." This person had dark blue hair and was a male.

"Who are you?"

"I'm just here to tell about something important. It's about your brother." Sans' blue eye flashed and teleported over to the person, surprising him.

"How do you know about Papyrus? Explain now!"

"I come from the surface and I was there when I saw him."

"Is he ok?" The person looked down.

"I'm sorry, but he was killed." Sans eyes widened in shock.

"You're lying!"

"Am I, Sans? I was there!" "He was blasted into ashes from a kid with yellow hair. His name was Chris and he killed him in cold blood." Sans staggered back in disbelief.

"No, no, no...This can't be happening." He sat down, grabbing his head in agony. "How could this happen? I should have been there with him." He sat there, crying. Then the sorrow went to anger. "I will make them pay for this!" The person looked at him in all of Sans' sorrow and rage. "I can help you get revenge." Sans looked up at the person in desperation.

"What are you talking about?!" His eyed blazed blue and the wind started picking up.

"I can help you get revenge on the one who killed your brother. It'll be very easy to find him once you get there, there aren't many people on the surface that could've hurt your brother." Sans stood up.

"I'm listening."'

AN: Like I said, I am a huge fan of Dragon Ball, but when I found out about the game Undertale and the fanbase surrounding this game, I grew to love the story, the emotional aspect of it all, and the amazing roster of characters Toby Fox had developed but no character stood out to me more than Sans. He was such a complex character with a witty nonchalant attitude that belied a very serious, intimidating and honestly badass opponent in a certain part of the story. (if you know Undertale, you know the Sans fight.) Looking across the internet, there were millions of people that centered a lot of amazing creations around him, like animating his fights, making headcanon voice potrayals, and the fan art(good and sketchy), and I had to join that group. People all around the world started making AU's of the main storyline which changed the personalities of characters and events that would happen in the story, and that's where the main inspiration of this supplemental story came to be. It's just a new AU that doesn't affect the story in particiular but changes some aspects of characters by adding in new elements from the DBNG main story.

In regards to the inspiration behind this AU's Sans, I took inspiration from these main AU's besides the original story and more. First one was Dusttale AU made from ask-dusttale (tumblr account). I mainly used this for his look from the fan art surrounding this character. Second was the fanfic, Karmic Retribution from Relicarn on Archive of Our Own. I used this as inspiration for the personality this Sans displayed in the one-shot. Third was Ultra!tale from Animated Zorox and I used this as how he fight since it's animated and there were some well animated fight scenes. And finally, I took some inspiration from the Game Theory's Culture Shock video about how Sans could be a revenant and I used that to center his behavior and motives in the story.

Anyway, I hope you enjoy this new supplemental story of DBNG. I wanted to bridge one of the most popular games in recent times with one of my favorite shows, and this is the only way I knew how. As always, please support the official releases from Akira Toriyama and Toby Fox as well as the people that I mentioned earlier.