Hey guys, sorry it has been so long. I havent had access to my laptop for a while so now I have it back I am going to upload a couple of chapters for you. Enjoy and thanks for the patience!

Sans feels a whole lot less bad about napping through the sentry station post or usiing that time to do some extra work on the side on trying to fix the feedback loop after meeting the human. Actually, he doesn't feel bad about it at all anymore. He'd gone back to the castle only once since then, and that was to find the toy knife and the ribbon, which he'd taken back to the child's room. He left them on the bed with a yellow flower and a noted that simply read 'I'm sorry' before leaving again. Someone deserved some closure, and it wasn't anyone outside the ruins. He had shown Papyrus the back trail, and his brother had declared the space 'perfect' before beginning work on an all new set of puzzles and traps for the long road to the ruins. Sans had taken some time to help him set up a sentry station made from a massive cardboard box, and then wound his brother up by simply moving his existing one from the space where it was to where it stood now. Sans had laughed when his brother declared that he had, to quote, "NO IDEA HOW YOU GOT IT HERE, BUT MOVING THE WHOLE THING IS INCREDIBLY LAZY! YOU SHOULD HAVE BUILT ANOTHER, LIKE MY OWN VERY GREAT AND WELL-CRAFTED SENTRY STATION. HONESTLY, WHAT AM I GOING TO DO WITH YOU? GOING THROUGH LIFE PUTTING IN THE BARE MINIMUM OF EFFORT-" He'd cut off the rest of the rant with a joke about being bone idle and how it was snow joke, and everything had felt right again.

The only reason he didn't straight up quit was because he was going to try to make sure his brother never came across a human, but for a whole different set of reasons now. Other than that, this job was completely pointless. He pauses at the thought. This felt … familiar somehow. He shakes his head and carries on working.

Sans could hear the sounds of Papyrus stirring through the walls, and he sighed at the plans in front of him. The extended deadline still wasn't long enough to essentially rebuild this from the ground up. It had taken him and his team months to get this even half right in the first place and it was as annoying as hell that it could go so wrong in less than half the time it took to get it right. Work was starting again tomorrow, and a texting notification pinged through on his phone.

*I think I've got something. My place in twenty minutes - I need to tidy the place and have a shower first o( Q A Q )o

He grabs everything and is immediately knocking on the door to her apartment. The door swings open enough that he can see her peek through, and she all but whines at him.

"I s-said twenty minutes, Sa- wait. How did you g-get here so f-f-fast?"
"i know a shortcut." He shrugs and grins at her as he makes his way in and flops onto the couch. "Go shower, I'll tidy."
She thinks about arguing, but than she remembers that she texted everyone, not just him. She nods and rushes out.
He doesn't move from the couch, just opens the bedroom door, removes some clean clothes which come to his hand, and shoves everything in there. Her bedroom door slams shut, the clothes are hung on the handle, and that done he closes his eyes for a fifteen minute nap... but finds it doesn't come. When Alphys comes out of the shower in a towel, he hands her the clothes distractedly, thoughts churning.

"hey, alph. are you gettin' a weird feeling? like we've done this before?"
"What? Like… d-deja vu or something?"
"kinda? but on steroids."
"N-not really? Mind you, I've d-dreamed about this a few t-times so maybe you're just getting a weird f-feeling from that?"
"hmm. maybe."
"You don't s-sounded c-c-convinced."
"never mind. 'm sure it'll pass."

When everyone is here, she shows them what she's been working on. Sans sees that she's simply added to what's started being built by adding in steam direction valves to redirect excess heat build up in sharp bursts. Honestly, it's genius. For all their working on the numbers and how to adjust the whole system, not one of them had thought about something so simple.

«It's a crude solution but-»
"it would buy us time."
"About twenty years to fix it, going on the numbers that she's got here from the redirection of the heat."
"I-i-i…"
"Twenty years would be long enough to let us do something else with it."
"woo, look at us getting all fired up!"
"E-engineering has always b-been a burning passion of mine!"
"You've taken to it like a house on fire!"
«I'm surrounded by idiots.» Gaster sighs fondly as he signs.
"nah, just a bunch of hotheads."
«And somehow my son turned out to be the biggest of them all.»
They all laugh, except Alphys who's sounding a little reserved. Gaster notices Sans isn't laughing so much either.

"you two go speak to the builders and get this in place, i wanna speak to alph."
MG and Gaster both nod and congratulate Alphys on her work, And leave them be.

"So, what's wrong?"
She stares at him for a moment, and starts to fidget with her tail. "G-geeze, Sans, th-there really is no g-get get anything p-p-past you is there?"
"nope." He grins at her. She sighs.
"Wh-what if it doesn't work? A-and I didn't really solve the problem. A-all it's done is buy us t-time-"
"alphys." He sighs her name, and she looks at him. He so rarely used the whole thing. "this is more than any of us had the thought to come up with. we were so busy trying to fix the whole thing that we didn't really think about short term solutions which are just as important. we were running out of time anyway, and if it doesn't work then we haven't lost anything."
"N-no, I'll just have to l-live with the f-f-failure of Gaster's hopes and d-dreams on my shoulders. And the explosion of a t-ticking timebomb."
"no, it's not going to be your fault. maybe farler's for screwing up years of work." Definitely mine for leaving before we'd finished. "having more time is what we were all asking for, and we just might have it."

She sighs, but stops fidgeting with her tail.

"'sides, you know what time is like. it was biting us on the ass, because all it does is devour. and when it's done, it just goes back for seconds."
"Oh. My. God." But she laughs until she's bent double.

Man, life would be so good if he could just fix everything with laughter.

It would be better still if this didn't feel so… off.

Building the exhausts into the design didn't actually take up any extra time, so a week later the whole lab is gathered for the switch on. The air is filled with an anxious excitement and everyone is buzzing with it. Gaster himself is the most fidgety Sans thinks he's ever seen him. It says a lot, but he gets it. This was literally his life's work in front of them… no, there's something else, too. He rubs at his skull, trying to get everything to make sense but nothing wants to fall into place neatly. He just steps closer to his father, watching him the closest he ever has to try and figure out what his father's behaviour and what his gut is trying to tell him, and says quietly "this'll work."
"I know. It's what comes after… no, never mind." Gaster still hesitates, so Sans reaches out and presses the button, and the sound of machinery fills the air around them. The underground, which to this point had had the previous generators which were dotted around turned off, stayed silent for a moment before the whole thing burst back into life with the most vibrancy anyone had ever seen in it. Cheers erupt through the whole cavern. Gaster's smile turns enigmatic.

It was as he was told. He knows what he has to do now.

"I need to speak to the main team about something. Everyone go celebrate, Alphys you can join them - I know Sans will tell you any way so there's no need to hang around. Thank you everyone for all the hard work." He sees Sans' brow furrow deeply. "Something has been bothering you all day. For the last week or so, actually. What's wrong?"
"i can't put my finger on it."
"What do you mean?"
"for a little while, it's been feeling like we've done this all before. it's how I knew the core would work. like deja vu but… more?" He sighs, shaking his head. "i know it doesn't make sense. but now… the feeling's gone. it's like… something's changed and i don't know how to know if it's a good or a bad thing. i don't even know what i'm feeling in the first place... eh, it's probably nothing."
"Hmm." Gaster falls into thoughtfulness for a moment, and Sans expects him to explain it away with something he hadn't thought of. Or agree it was nothing and tell him not to worry about it so much. Instead, his words both surprise and chill him. "I suppose it was to be expected. You always were perceptive - too much so sometimes."

He wishes he has time to explain, but Gaster also knows that if he does, his son will absolutely try to stop what is about to happen. And besides, he doesn't remember what happened before, he just knows what he has been told to do this time and he's left the pieces in place to do it. This is the last thing.

"what the hell is-" Gaster cuts him off, bending down to his height and taking his face in his hands to pull his attention. Not that it could go anywhere else right now.
"Sans, listen to me." He feels magic enter his soul, warming it. What- "something happened that shouldn't have and it needs to be corrected. It is being corrected, in a moment. Some of us have unavoidable fates. I just… needed a minute to repair something else first. As much as possible."

Sans watches his father's right eye droop and face start to lose form.

"You will find some of the answers at home. Look for what wasn't there before. I'm sorry I don't have time to say more." The magic stops and he feels… different. His father's face looks like it's melted, but the smile on it looks… happy? He tries to push himself away, unease churning within him.
"that sounds like a goodbye."
"No… more of a 'see you later'. I love you and your brother very much, as poorly as it translated. I am sorry for that. Now you must go. You don't need to see what's about to happen."

Sans feels the familiar pull of a shortcut, but he knows he didn't open one. He tries to go back to the core, but as he opens his own shortcut, there's a feedback through his magic and his eye as it feels like something rips apart.

Gaster lets a tear fall as he looks at the empty space that held his eldest son. The team come into the space where now only he stood as he lets magic flow into the space by the core, starting to build and overload the system. An alarm starts to blare, and the team all look to him as he pays it no mind.
"Doc…?"

Sans collapses in pain, and can only gasp for air on the floor and pray that it doesn't kill him. So much pain.

"It's nothing to worry about. I am sorry, but you are all a part of something bigger at play. Your fates are as intertwined with it as my own." A warning light starts going off. They move to try and fix it. He holds them in place with his magic, letting the core take that also.

Too much pain.

"I told you it's nothing to worry about. This is how it's supposed to go. This… is how it's always supposed to go. My apologies, but if it's any consolation… your families will not mourn." There's a touch of bitterness as he knows that cannot be said for his own, but hopefully with the boost, his son will at least live through the loss.

He passes out on the floor in his room as it feels like something beyond the world is ripping his soul apart at the magical seams.

His boys are the last thing in Gaster's mind as the abyss swallows them whole, safe in the knowledge that this is how things have to be.