Chapter 3: Back to the past; Science!Sans

Okay guys one last change, I swear. UnderFell is also shortened to be called Fell, just to make things easier. Sorry for the many changes, and I hope you enjoy.

US!Papyrus POV:

Papyrus woke up early the next morning, like he has for the past few nights. It has been getting harder to stay asleep most nights, as worry and nightmares plagued him every night. He knew the process of getting back his brother was going to have to take a lot of time, but he still wished it would go faster.

He rolled out of bed tiredly, not caring that the bed was unmade, seeing how the rest of his room was still a mess. Shutting the bedroom door behind him, he walked out into the hallway and down the stairs, and noticed right away that UnderFell wasn't on the couch like they had left him. Raising a boney brow, Papyrus glanced around the room. "Uh, Sans?" He called out to UnderFell, and right after that there was a loud bang in the kitchen, like a bone hitting something else really hard. Following that, the sound of glass breaking. Papyrus wasted no time to get to the kitchen, his eye sockets narrowed as he walked through the door. UnderFell was in there, holding the top of his skull and giving a slight pained look with the fridge door open, not seeming to have taken notice of Papyrus. A glass soda bottle had fallen and shattered on the ground, creating a mess, and Papyrus could hear UnderFell muttering a stream of curse words under his breath. He smiled lazily and chuckled slightly, causing Fell to jump and look back at him. Seeing how it was just Papyrus, he relaxed and grunted again, standing up.

"Need anything?" Papyrus asked, keeping up with the lazy smile. Fell sighed and glanced back at him. "I was looking for a bottle of mustard. You got any?" he asked, crossing his arms. Papyrus shrugged and walked over to the fridge, stepping around the mess of broken glass and sticky soda. He glanced inside and pulled out a yellow bottle that was in the far back of the fridge, closing the door behind him and tossing the bottle over towards Fell, who caught it uneasily, and looked down at it, smiling slightly at the sight.

"Thanks, boss." Both suddenly stopped as Fell said the word. Papyrus' smile was gone for a moment, and so were the lights in Fells eyes. After a moment, Papyrus tried to put on an uneasy smile, and gave a slightly awkward chuckle. "heh, I would rather you call me Papyrus rather than 'boss'." He said soon after. Fell only glanced away and put the tip of the mustard bottle up to his sharpened teeth.

"R..right. Sorry…" was all he replied with. There was more awkward silence that followed, as Fell squirt some of the mustard into his mouth and gulped loudly. After a moment, Papyrus spoke up again.

"How's about you go and meet up with Sans in the shed. I'll clean up this mess quickly, and we can get back to work." Fell didn't dare to disagree, as he nodded quickly, and with a quick and quiet thanks, he ran out of the kitchen and outside to the shed. After hearing the door slam shut, Papyrus relaxed and gave a small chuckle to himself again. He let his left eye glow a deep orange color and with a literal snap of a finger, the glass and soda was off the ground, cleaned up. With a small, satisfied smile, he nodded slightly and walked out towards the shed. When he walked in, he was surprised to see the amount of tension in the room.

Fell was laughing his ass off, clutching his ribs and about ready to double over as Sans glared down at him with obvious tiredness and anger. Papyrus walked in with confusion written all over his face and the two looked towards him.

"What did I miss?" Papyrus asked with his regular, lazy smile, but also with a raised brow. Sans huffed out angrily and crossed his arms. "Let's just say I didn't have a very pleasant wakening…" he muttered out. Fell burst out laughing again and looked at Sans. "Oh common, it was pretty funny," he said between each giggle. Papyrus seemed more interested now as he looked at Fell.

"What'd you do?" He asked. Fell smiled towards him, his one gold tooth reflecting light. "Let's just say I made a 'boneified' entrance." He stated before laughing again. Sans growled out in frustration, and Papyrus seemed a bit surprised at how angry he was, over a little prank.

"You were 'this' close from hitting my skull! Let alone the machine!" Sans snapped at him. Papyrus' eye sockets widened slightly and looked at the worktable near the machine. Just above it, in the wall was a glowing blue bone, sticking out of the wall. He looked back at the shorter skeletons when he heard Fell huff out a bit. "It wouldn't have hit you if you stayed still, and it didn't. Besides, that's my usual wake up call." He smiled, and Sans just rolled his eyes in response.

"Whatever…" he muttered "Let's just get started." He turned towards Papyrus, his annoyed look turning serious. "I've managed to find the next closest Universe."

"What is it?" Papyrus' look turned serious as well as he walked in further, closing the shed door behind him and looking at Sans.

"UnderTale." Papyrus gave a funny look at Sans, but Sans quickly replied, knowing it would have sounded confusing.

"I mean a different timeline in UnderTale. There's more than one timeline there, and more than one Sans. Actually, there are two other Sans' from UnderTale besides me, both from two different timelines. So far, we can only reach one of them."

"Why only one?" Papyrus asked, glancing to the side and seeing that Fell had started listening as well.

"Because the other one isn't in any actual universe. It's not the void, either, though." Papyrus raised a brow and Sans sighed. "You know how Frisk can Reset or Continue? This other Sans is there. It's not like the void, and we can't reach it with just the machine." Understanding now, Papyrus nodded.

"Alright, then who's the other one that we can get to?"

"Well, he's more like a younger version of me. I would just call him Science Sans. He works at the labs with Alphys and…Gaster." Papyrus frowned but nodded at Sans. He had read up on what had happened at the labs long ago, what had happened to Gaster. How he has been stuck in the void. He also knew how Sans always felt uneasy about Gaster, though he never knew why exactly. But that didn't matter at the moment. What mattered was getting Science Sans and finishing up this dammed project so they could finally save his brother.

"Alright, then let's make this one quick. We grab Science Sans and bring him here before we explain anything. So we don't have to stay too long." Papyrus suggested. Sans frowned again.

"That's the other thing. We can't stay for very long. Since this is a whole different timeline, it's even harder to reach. So we can't stay too long, because if we do, we'd overpower the machine and get stuck there. The maximum time we could stay there is fifteen minutes. So like you said, get in, grab Science Sans, and get out. After that we need to let the machine cool down again before reaching the next place."

"Alright, and what about me?" Fell finally decided to join the conversation. Sans looked towards him. "You get to man the machine." Sans answered, adding a bit of annoyance to his voice. "Stay by the machine, and if we aren't back by the fifteenth minute, press the red button." Sans explained. Fell looked at the machine, looking over it before nodding and crossing his arms. "Alright. Sounds easy enough."

"And don't touch or mess with anything else on it. If you make even the slightest change, everything will mess up and bad things could happen." Sans warned him. Fell just put on a not-so-innocent smile and raised his hands in a surrendering gesture. "Calm down pal, I won't mess with your techno junk."

After that, Sans walked back to the table and grabbed the two travel pieces, handing one to Papyrus who slipped it on immediately. Sans did the same and looked at Papyrus.

"Alright. No splitting up, either. We need to make this quick. No more than fifteen minutes." Once Papyrus nodded, they both pressed a button on their travel pieces. Like every other time, nothing but a slight hum at first, then a flash of blinding light and a skull crushing pain. It seemed longer than the last time before Papyrus blacked out from the pain.

UT!Sans POV

When he came to, the first thing he noticed was that they were still in Snowdin. That was a bad spot to start. He knew that Science Sans was in the HotLands, at the labs with everyone else. And that was a far walk. The quickest way there would be to teleport, but it takes a lot of energy to teleport such a far distance. But that didn't really matter at the moment, either. They just needed to get there quickly.

Standing up quickly from where he laid just a moment ago, he looked around through the snow, hoping to spot Papyrus. Walking around slowly, he soon heard a groan, and some shuffling in the snow. He turned around and saw Papyrus sitting up and holding his head. Relieved that they hadn't split up, he ran over. Papyrus saw him and sighed.

"We've gotta work on this thing, I can't keep up with the headaches." Papyrus muttered to Sans, who only chuckled quickly. "Yeah, but there isn't much I can do on that right now. When we find the nerd we can get him to help us with that. Now come on, we don't have that much time." With a nod, Papyrus stood up and glanced around, and seeing his small frown, Sans knew he was thinking the same thing he had thought just moments ago.

"Yeah, I know. Bad place to start. We're going to have to take the less scenic route." Papyrus' eye sockets widened slightly and he looked towards Sans. "You've got to be kidding me. That would take too much energy. We'd be drained even before we got inside the labs!"

"Yeah, well, do you have any better plan?"

"…" With the question left unanswered, Sans nodded. "Right, so let's just hurry this up, alright?"

Papyrus grunted slightly, which Sans only took as an agreement, and the two started. They had to concentrate on their magic, had to gather enough of it to get to HotLands, and not a bit more, because losing suck a large amount of energy from stuff like this was not very healthy, but it was the quickest way. The stood for a moment, their brows scrunched together in concentration, and once they knew they've gathered enough energy, they looked to each other and nodded. Sans gave a bit of a smile, and Papyrus tried to return a lazy smile of his own, and the two let their magic take over.

It really didn't take long when their magic took over, a few seconds was all. But recovering from that would take more time. Sans felt the heat automatically when they reached HotLands, but his body couldn't care as he dropped to his knees, panting from sudden exhaustion. He heard Papyrus next to him, just about in the same position, but he couldn't lift his head to make eye contact with him just yet. He needed a minute.

It felt like forever, but was probably only a couple minutes, before Sans was able to breath normally and stand up with effort. Looking over to Papyrus, he saw him kneeling still.

"You alright?" Sans asked, the words already taking his breath away again. It would take more time to fully recover, he knew that. Papyrus made a simple nod before getting to his feet, swaying for a second before quickly managing to keep straight. After making sure they could move quickly without falling, they made their way into the Labs.

It was fairly different than what it would look like in their timeline. It was a lot messier, more Papers scattered around with multiple pens and pencils, a couple blueprints hanging around here and there. Both Sans and Papyrus made sure to stay quiet for the time, as they didn't want to attract any attention. Their pace was quick, as well, as they knew they already spent more than half their time outside. They glanced in every direction, and was amazed to find that it seemed even bigger than it looked from the outside. They checked through multiple doors, all empty.

They were off to check the next room, when they suddenly heard voices. Two voices, one male and one female. Footsteps followed, and were heading right towards the two. The two skeletons were quick with their actions, as they turned around the corner and laid their backs flat against the wall as they listened. As the voices came closer, they could start to hear the male sounded similar to Sans' voice. It had to be Science Sans. The other, now recognizable as well, sounded more like Alphys.

"And the machine just…stopped working?" They heard the other Sans question.

"Y-yes, t-the m-magnetic field just had a r-random i-increase of e-energy, a-and b-broke the machine." They heard Alphys answer.

"and no one's found the cause of it?"

"N-no, i-it l-left as q-quickly as it c-came."

The footsteps stopped, and they heard a sigh come from Science Sans.

"Alright. We'll keep trying to find that cause. You go head back and see if you can fix the machine. I need a coffee."

They heard Alphys agree, then heard the footsteps split apart, one heading the other way, the other heading directly towards the two again. They heard another sigh, and was thankful to hear it was Science Sans. This was going to be a lot quicker and much easier than they expected. Sans gave a small smile and Papyrus got ready.

They had to make this really quick.

Sci!Sans POV:

"You go head back and see if you can fic the machine. I need a coffee…" He muttered. Alphys nodded her head and said a quick 'okay' before heading off. Sighing, Sans began walking to the break room, feeling annoyed and tired. This should have been such an easy process. But something went wrong with the magnetic field. An interference, for sure, but what could have created so much energy that could interfere with the magnetic fi-

His thoughts were interrupted. He turned the corner a boney hand grabbed his wrist and pulled him forward. Another hand covered his mouth before he could make a sound. His glasses slipped slightly, and his eye sockets widened as he quickly began to panic. Before he could get a look at who had ambushed them, he heard a strange beep, like a timer going off. Then a came a bright flash of white light, and a skull splitting pain. He couldn't make sense of anything before he blacked out.

UF!Sans POV:

The fourteen-minute mark passed already, and Fell stood next to the machine, his hand just above the red button that Sans had told him to press if they didn't come back after the fifteenth minute. He knew that he couldn't mess up if they didn't come back in time, hearing how they explained the process, there was no room for mistakes, and he wasn't going to be the one to screw up.

In all honestly, he really wouldn't have cared if they made it back or not. Why would he? They basically kidnapped him and forced him into this. But seeing what was going on. If Error was really out there destroying more timelines and universes, he had to help. He didn't want his universe destroyed, no matter how bad it was there. He couldn't lose his brother, let alone let it be his fault. He wouldn't do that, no, he wasn't that cruel.

The fifteenth minute mark struck and Fell didn't waste a second before he pressed the button. Nothing happened for the first second, but then there was a beep, like an alarm clock or timer going off. It worried Fell that maybe it didn't work, maybe it was already too late. But then, a blinding white light filled the entire shed, making Fell shield his eye sockets with his hands. It left as quickly as it came, and once he let his hands down, he saw both Sans and Papyrus standing there, looking slightly dazed and more tired out than they did when they left. Though there was a third person the Papyrus held onto by his shoulders. A small smile placed on his sharp teeth, knowing it was who they were looking for. They did it, they got Science Sans.

Walking over, Fell looked over Science, getting a better look. He looked more like Sans than Fell, the same flat teeth, lack of scar, though his clothes were different. He wore a lab coat and long white pants, along with black shoes. He also wore glasses, which looked pretty funny, as the sides had to be taped to the sides of his skull since nothing else could hold them up to his eyes.

A small groan came from Science making everyone look towards him. His eye sockets began to open, and one hand went up to his skull as he began rubbing a headache away.

"Ugh…what happened..?" They heard him question to himself. Then, as if remembering, his whole body tensed and his sockets widened before he looked up and around at everyone. His eyes first went to Papyrus, and he seemed a bit shocked to see another skeleton, but he looked even more in shock when his head turned to Sans and Fell. He stared for a few seconds, being silent while he did so. His shock began to slowly form into amazement, and eventually he found his voice.

"You guys…you're me?" He questioned loudly, standing on his own now, and Papyrus let go.

"But…that's impossible, I thought that the whole different universe was fake. There was no evidence about it being real,"

"Well, don't you think we're enough evidence to believe?" Sans asked with a lazy, tired smile. Science stared at him for a moment.

"Wait…you were the one who caused the irregularity in the energy field, weren't you?"

Sans gave a bit of a confused look, but soon began to understand, and he gave a bit of a sheepish grin. "Heh, probably. Uh, sorry for wrecking your machine. But we had a reason. We need your help." He said.

After another explanation about their plans to help Swap and stop Error, Science agreed to help. What shocked everyone else, too, was that Science seemed to be taking this all the best. But then again, he was a scientist, and was good with handling new discoveries. Another thing he was good at, he claimed, was helping with the machine. He said he may be able to make it easier to travel, and allow them to travel farther with less energy. Sans was grateful that Science was there now, and so was Papyrus. This would help things go so much faster, and they knew they needed that time. It's already been days since Swap was taken, and fear and doubt was seeping into Papyrus. Sans promised him, though, that they'd find and bring him back.

He promised, Swap was safe.

Okay guys! I hope you enjoyed this chapter! The next one will have a little less action, and may even have a few…Error ;P

That's all for now! See you guys soon!