It was dark outside.
Frisk stumbled several times as they ran, chest heaving up and down, to Waterfall's caves to look around desperately. They could RESET right now, if they wanted to- but that wouldn't solve the root of the issue here. If they RESET, Sans would still be gone, Papyrus would still be heartbroken, and Gaster would still be a threat.
The door wasn't there, though.
Frisk stared at the blank wall, feeling slightly frustrated. Where did Gaster go? They wondered, reaching up to feel the cool stone with one hand.
A hand was suddenly placed heavily down onto their shoulder and Frisk froze, going stiff.
"Hey, Frisk, what're you doing out here at this hour?!" Undyne demanded leaning down to Frisk's level. "Alphys said you weren't well, what do you think you're doing, wandering around by yourself?!"
Ah. It was just Undyne. Frisk, flustered, turned around and waved their hands as they gazed up at the monster.
The fish-woman sighed. Clearly she had heard about Frisk's issue, but she didn't directly address it, to their relief. "Yeah, I know, I know. You can take care of yourself and all that. But Alphys said she was worried and wanted to know where Sans was- Papyrus and you looked like you needed some help."
Frisk turned their head away, studying the wall again.
"Hey, I know! I was just heading back from the Lab- Alphys and I held an anime marathon while the doc was working, like usual. Why don't you head back to my house for now? I can call Papyrus or Sans and let 'em know you're safe."
...doc? Frisk whipped their head around so fast they almost hurt their neck. They tugged on Undyne's hand, pulling her back in the direction of the Lab as they peered up at her hopefully.
"What? You want to go to see Alph?"
Frisk nodded, looking at Undyne hopefully.
"Huh. Fine, bestie, but just for you. After that, you should come back to my place so you don't get any worse- I just finished rebuilding, too! You should see my new kitchen! My stove can get TWICE as hot now!"
Undyne let them pull her along to the Lab, and Frisk's mind raced as they skidded to a stop, Undyne standing next to them. It wasn't as hot in the Hotlands during the night time, but it was so humid both Undyne and Frisk were gasping for breath. They reached up and hit the button, the doors sliding open to the building and cold air flooding out. Frisk took a deep breath, aware of the hour but eager to see if their suspicions were correct.
After all, the inside of the building looked different.
There were still one or two anime posters on the walls, but the desk was in immaculate shape and the entire lab had a more sterile, clean appearance similar to the last time Frisk had been there. Alphys was at the desk, writing something down, and looked up in surprise, her glasses almost falling off of her nose.
"A-ah, Undyne! Y-you're back? What do you need- F-frisk?" She stuttered, sliding off the chair and coming over. "W-what's wrong? I- I mean… other t-than… erm…" Alphys looked between the two of them, at a loss. "I. I'll just. Go get some paper and a pen for you," she squeaked, racing back to the desk and shifting through the piles of paper. She made a mess as she did it, papers fluttering every which way to the floor, until she finally found a clean sheet and a pen to present to Frisk.
Frisk looked around, then took the paper and knelt on the floor so they had a flat surface to write on. Thanks.
"N-no problem," Alphys stammered. "B-but why are you here at this hour? W-where's Papyrus and S-Sans? Is your throat-"
[That's enough, Alphys.] A smooth voice cut in, the door to the escalator sliding open. [I'd imagine they are here to see me.]
"Dr. Gaster- I-I'm s-sorry, did we disturb y-you?" Alphys asked nervously, wringing her hands together.
Frisk froze, staring down at the paper as black shoes came into their view.
[No. I observed on the cameras we had a visitor.] Frisk glanced up, shrinking back a little as they saw Gaster towering over them, clipboard in hand. The skeleton was… almost the same as Frisk had last seen him. The strange, ethereal form Frisk had first met was nowhere to be seen, and Gaster looked interested at the human sitting at his feet.
"Oh! That's right, Dr. G, you haven't met Frisk yet, huh?" Undyne said cheerfully. "If you'd have come out of your lab for longer than two seconds, you might've met them earlier- they've actually been living with Papyrus and Sans for the past month!"
[Oh?] Gaster adjusted his glasses, and sighed. [So? Where is Sans, then?] His eyes narrowed in knowing thoughtfulness and he seemed to take Frisk's unmoving stare as some kind of confirmation. […I see. Well, thank you Alphys, but you are excused from work tonight. Don't worry about- Frisk, was it?- I discerned ahead of time they would be coming to see me.]
"W-wha-? But…"
"Come on, Alph, let's head back to my place then if you have the night off!" Undyne shouted cheerfully. "Hey, this is a rare occasion that Gaster doesn't have you working! We should go have fun and finish that anime marathon!"
"B-but… but Frisk…" Alphys stammered, casting a pleading glance at Gaster, who merely stared back at her.
[I am aware of their species, Alphys. You need not concern yourself with those kind of thoughts. They will be fine,] Gaster stated calmly, tilting his head.
Undyne finally managed to convince Alphys to leave with her, convinced Frisk was in great hands, and the two left, leaving Gaster and Frisk alone, each studying the other occupant in the room.
Frisk's grip tightened on the pen and they stood, backing away from Gaster in measured steps. They hadn't protested as Undyne and Alphys had left, because they knew just as well as Gaster that this conversation needed to be private.
Gaster was silent, and he circled around Frisk once before speaking. [The last I saw of you was after Sans forcefully dragged me away from my life's work,] Gaster said, light reflecting off of his glasses so Frisk couldn't read the expression on his face. [I've always wondered when I would encounter you again. When you showed up a month ago, however, Sans was still around so I knew you hadn't yet interfered with the Core, and I still needed to wait.]
Frisk eyed Gaster wearily, mind reeling. So Sans did manage to SAVE him after all. Then- then this might work, right? Gaster might still know how the RESETS worked!
I need your help to SAVE Sans.
Gaster glanced at the sheet of paper, studying it for a moment. He sighed, one hand briefly pressing to his forehead. [Whatever you two went back for, I assume you greatly changed the present.] He formulated, putting his arm back down and turning, his lab coat swishing behind him as he walked away and motioned for Frisk to follow him as he stepped back into the elevator. Frisk hesitated for only a second, taking a deep breath. No matter the consequences to this, Frisk knew they had chosen to do this. They would see it through.
[The Sans I knew only got back after the explosion, unaware of his own ashes which I found besides a puddle of human blood,] Gaster said quietly, not looking at Frisk as the elevator hummed and started descending. [I have… attempted to try and figure out how and why these events happened, but was unable to formulate any hypotheses that fit all of the known facts. My experiments with DETERMINATION started to produce inconclusive results, and I started hoping that you would be the next human that fell down here to explain this peculiar phenomenon. Instead, with every human that came, I delivered their SOUL to the King after recording any notable information. Sans left me with P02 in tow after the fourth human's fall, and ever since then I have had Alphys come join me as my assistant. She always had shown some promise, at least.]
Gaster glanced down at Frisk for a moment before he wrote something on the clipboard again. [Eventually, I speculate that my Sans and your Sans became the same person. Time seems to have a certain way of making sure interference doesn't change things too much. These events- how much matches up with the reality you remember?]
The doors slid open, and Gaster stepped out into the corridor, Frisk following just behind him. Gaster pulled out more sheets of paper, and carefully placed them on a table in front of Frisk. [Now. Write,] he said, sitting down and crossing his arms.
Frisk stared back at the skeleton and then leaned over the paper, going to work.
.
[Fascinating,] Gaster said, holding the paper up to his face. [I never would have imagined the Core had those properties- hmmm.] A peculiar expression crossed over his face, and he sighed, kneeling down in front of Frisk. [It seems that I have wronged you, human. Although I cannot say I would have changed what happened, my apologies for the unneeded stress I seem to have caused. Normally I try to be more…. humane about my experimentations.]
Frisk shrugged. They were relieved to see this version of Gaster was more reasonable, but they didn't entirely trust him yet, either.
[Well. First things first. I need to teach you Wing Dings.]
Wing Dings?
[A type of sign language I created for S01 and P02 to communicate to me with. It somehow spread in the Underground, so although most monsters do not use it everyday, it is generally understood. Writing is a cumbersome method of communication, after all.]
Why is that important for me to learn? Frisk wrote, and Gaster stood up to glance over their shoulder as they wrote.
[Because, human, as I said, I researched DETERMINATION for a long time. I am almost at a breakthrough, but I am missing something vital- a human with a large enough source of DETERMINATION and a few last pieces of information.] A small smile finally appeared, and Gaster turned to walk over to his computer. [If we are to SAVE Sans, my assistant for this project needs a more effective way of communication with me than writing.]
Frisk froze, eyes widening. You- You're willing to help me?
[Why wouldn't I? From the looks of it, you SAVED me from quite the traumatic fate. And… I know that I have wronged both you and Sans in both this and other timelines. Whether you believe this or not, I am not some monster without any feelings. Sans and Papyrus, as they named themselves later on, are both creations that I am very proud of. One day, they will carry the mark of my creation past my own time. One of them dying before I do does not sit right with me.] Gaster adjusted his glasses, typing something into the computer. [Anyways, this entire project seems to be quite interesting.]
.
(Gaster, wait!) Frisk signed quickly, jerking away. (That needle looks like it'll hurt!)
[Don't be ridiculous, this needle is miniscule,] Gaster grumbled, pulling Frisk's arm back towards him. [I need to take another sample of your DETERMINATION and you know just as well as I do that this is the easiest way to do it.]
It had been several weeks since Frisk had started working with Gaster. It hadn't been exactly the easiest thing to do, as Gaster demanded perfection and easily got frustrated whenever Frisk messed up, and Frisk had been so busy most of the time they had slept on one of the spare beds from the Amalgamate disaster, as Gaster called it. Some things hadn't changed, after all.
Flowey, Chara, and Papyrus both remembered the same things Frisk did, although the former two remained largely silent on the matter. Frisk was glad. They didn't want to run into Flowey again just yet.
Papyrus was… not doing very well. He was a shadow of his former cheerful self, and drifted in and out of the lab with uneasy looks at Gaster, unable to remember the past years where Gaster had been in his life. Alphys and Undyne said Gaster wasn't that bad of a monster actually, just very meticulous about his work, but any interactions with Papyrus proved awkward to say the least.
Gaster told Undyne and Alphys that Sans had had to go away for a while, but neither seemed to believe it with the way Papyrus was acting. Undyne eventually took him under her wing for a while, keeping an eye on him in her house instead of leaving him to his own purposes.
Frisk tried not to take note of all of the differences and similarities left behind from the effects of Gaster's presence. There were so many small and large things that it just made their head hurt. Mettaton, for one, was no longer a celebrity. He was just a robotic guard, with extremely dangerous abilities which Gaster had overseen Alphys build.
Asgore and Gaster where surprisingly close friends, and at times Frisk couldn't help but wish that this was the Underground they had first entered. Things weren't…. weren't better, per say, but they weren't worse either. They were just… different. If this had been the original Underground, then Gaster never would have figured out the secrets of the RESET though, and Frisk wouldn't have lost Sans.
Hmm. Speaking of which, maybe Frisk shouldn't be helping Gaster figure that out, but it was too late now.
Frisk held still, sucking in their breath as they watched Gaster summon their SOUL and take hold of it. It tingled a little bit, and Frisk could feel their HP fall a few points, but it wasn't too bad.
Several times, Frisk had fallen asleep on the counter while working, and they had woken up with a blanket over their shoulders even when Alphys had been out all day. Frisk was still wary of Gaster- it was hard to forget everything that had happened- but… But Frisk couldn't really bring themself to hate anyone.
And maybe that was a good thing. Because that had been what Frisk had always been like, from the first time they opened their eyes and saw golden flowers laying scattered around them. Despite everything, Frisk hadn't changed all that much, like they had feared.
Gaster finally sighed, taking his glasses off and rubbing his eyes with one hand. [All right, Frisk,] he said softly, looking up. [I have the solution but- well. Statistically speaking, the news isn't very good. But yes. If you look at the numbers and calculations then Sans can indeed be SAVED.]
.
.
.
DETERMINATION results pending...
((Erm... this chapter was difficult to write to say the least. I prefer writing the evil sack of crabapples Gaster to just cold, sciencey Gaster. It's amazing the difference of what who knows how long void timeout does to one's personality! Anyways, two chapters left of the story, believe it or not. I'm super excited to nearly be finished with this! Also kind of sad, I've had so much fun writing it. Oh well. I have lots more angst Undertale ideas that need to be written. Maybe I can even branch out and do a happy story for once...? As always, thanks for reading guys and see you next chapter!))