This is my first story!
Disclaimer: Undertale is property of Toby Fox Also, this story gives spoilers to the bad kid (aka genocide) route of Undertale.
Chapter 1: DETERMINATION
"Together, we can erase this pitiful world..." Chara told Frisk. Frisk had just wiped out the entire underground within a few short hours. Chara now stood before them, asking them to join forces and end the world. Frisk had 2 choices, Either give Chara their soul, or Chara would end all existence. Frisk couldn't decide. He wanted to give Chara their soul to live another timeline, but also, wanted to keep their soul. "What will it be Frisk?" Chara wouldn't stop pestering Frisk. Frisk did the only sensible thing... try to reset the timeline with their determination. Instead, all of the people who wanted to kill Frisk from their previous genocide stood before them. Chara obviously wanted Frisk to make their decision... NOW! "Time's up Frisk!" Chara said happily. With a snap of his fingers, all Frisk's enemies attacked! Spears were thrown, Gaster Blasters were fired! Soon, Frisk was slashing at all who were in their way. Dust was erupting everywhere! Within 10 minutes, only Sans, Chara, and Flowey remained. "so... looks like you wanna have another bad time..." Sans stated. "Guess you all gotta die!" Frisk said. He attacked Sans and hit! Sans was on the ground bleeding, then got up and attacked with his normal strength! "H-how?!" Frisk asked. "simple... the power of determination!" Sans told Frisk. He explained how him and Flowey were reborn with determination and the injections Sans gave himself to be determined. "Now... the REAL battle begins!" Sans and Flowey said. Soon, the chaos had begun... Frisk kept attacking Sans and Flowey, both of which hadn't been injured at all after 1 hour of attacking! Soon, Frisk was forced to allow Chara to take their soul. "Now was that so hard Frisk?" Chara asked. Next thing Frisk knew, they were alone in a void... Then, Frisk saw a strange shape in the distance. It was coming closer and soon, Frisk was faced with former Royal Scientist Wingding Gaster. "So... you must be Frisk..." Gaster stated. Gaster told Frisk their story and Frisk told him his. "I think I might be able to get back your soul." Gaster told him. But the expense was that he had to give Gaster some determination so he could manifest in the living world. Frisk agreed. Meanwhile, in the world of the living, Chara had control of Frisk's body, mind, and soul. They were at the very start of the timeline, where 'Frisk' had just fallen down from Mt. Ebott. They left the room and encountered Flowey. "Time to change it up..." Chara thought. They walked up to Flowey, pulled out the stick they had, and started brutally smashing Flowey with ease. Flowey's last words were "Why Chara?" One less creature for Chara to deal with, the better. Then, just as expected, Toriel entered the room and started talking to Chara. Chara decided to kill her too. Chara's LOVE was already at 3. Within the next half hour, the ruins were covered in dust and blood. The door to the ruins opened from a gaster blaster when Sans had thought he heard the distinct noise of a Loox screaming and being silenced. Sans immediately came face to face with a bloody Chara. "So... I guess that the ruins became a bloodbath..." Sans said jokingly. Chara, who was not amused, attacked Sans and he dodged, while attacking at the same time. After 26 resets, Chara finally got rid of Sans and went on to slaughter Snowdin forest... when Papyrus encountered Chara, they saw Sans's distinctive blue hoodie wrapped around their waist. Papyrus was NOT happy. For the first timeline Chara ever saw, Papyrus had one goal... to KILL Chara! Papyrus actually was giving Chara a harder time than Sans EVER did! "WHAT DID SANS EVER DO TO YOU!?" Papyrus asked angrily. 'Oh you naive little fool..." Chara said. "Don't you get it? This is all nothing but a children's game!" But not even Papyrus with his rage could beat Chara. Now, it was time for Chara to visit waterfall and slaughter everybody there. Even Undyne and Monster Kid... But once in waterfall, something unpredictable happened! Chara was face-to-face with W.D. Gaster! "Give Frisk their body back... NOW!" Gaster demanded Chara shook their head no, so Gaster said "I guess I get to do this the fun way!" Gaster started to attack Chara and, well, it was like fighting a steamroller without your arms and legs. But, Chara was relentless, and each reset somehow made him stronger. "Looks like I'm in for one HECK of a fight..." Chara said