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Just Cause

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Timeline 4

“A-are you sure you w-want to do this?”

The cold white light of the computer’s screen draped the room in frigid, lifeless shades, like a sheet laid callously over a body that still housed a fading soul.

Its sterile caress traced the edges of small, slumped shoulders and the back of a half-bowed head, and Alphys had to fight the urge to grab them, hold them, and keep the person inside that frame from walking to his death.

Not that any of them seemed likely to survive, if the chart on the screen was accurate.

At the sound of the scientist’s trembling voice, the whisper of soft pink slippers against tile slowed to a halt, and the timeline monitor’s deathly light flickered in Sans’ large eye sockets as they turned to meet Alphys’ eyes.

As always, he was smiling. She doubted he was capable of doing otherwise, yet while his ever-present grin didn’t move, the dread behind it was tangible. “Not really.”

Not really, and yet even as his face had turned toward her, his small body remained pointed at the exit.

As if noticing that she’d noticed, he glanced away, forcing his eyes to join his mouth in a smile that held only a struggling memory of humor. “Heh. Come on, you know me – I like to take it easy. Fighting a person who can take on Undyne and win, and retry an infinite number of times... sounds an awful lot like work.”

The smile in his eyes fell away, and the thin bone sheaths that passed for eyelids slipped closed. “But there’s something off about this kid. I mean, besides the whole ‘murderous rampage’ thing. Their stats don’t make sense. They never wear armor. And something about the look on their face...”

The echo of an earlier conversation swirled through Alphys’ aching head, a flash of hopeful color like the sparks that rose from Hotland’s magma pits, and she almost managed a smile of her own. “You think you can get through to them?”

Sans’ stare drifted to the TV, where a small figure in a striped shirt was limping slowly across the walkway that led to the Last Corridor. The human child didn’t seem to be injured, but exhaustion lay heavily on every movement, and Alphys couldn’t help but think that their expression seemed strained, as if fighting for neutrality through a haze of ill-concealed pain.

“Maybe. Who knows.”

Sans’ voice reclaimed Alphys’ attention, and he finally turned to face her fully, the struggle in the human’s face mirroring itself in his cheerful facade as he continued.

“There is a chance that they’re doing this out of boredom. They got power over the timeline, started messing around, and eventually decided that their toys weren’t fun enough when they played nice.”


The simple word hit like a sledgehammer, and Alphys’ teeth ground together as a fierce toothy smile, a pair of strong hands, and a warm yellow stare gleamed in the eye of her trembling mind.

A person who had always supported her and made her feel special, even when she didn’t deserve it, melting and crumbling into dust at the hands of a bored child.

A hero reduced to a plaything, to be wounded or killed at the whim of a creature too powerful to stop.

And now Sans is... is... is still talking.

“But tibihonest, I don’t think that’s the case. They don’t look like they’re having fun. Whatever’s got them so determined to kill us, I don’t think it’s just boredom. Heh...”

Once again, his eyes fell closed. “Papyrus thought he could get them to change, just by being nice. And maybe I’m an idiot for thinking that he might not have been entirely wrong.

“Who knows... maybe if he’d been able to find the kid’s problem, instead of just throwing niceness around blindly, it might’ve worked. Either way, I have to try.

“If they DON’T have a good reason, maybe I can give them a bad enough time that they decide it just isn’t worth dying for nothing anymore. And if they do, and I can find it... well... do I have any choice, other than giving it a shot?”

Yellow claws twisted together, nervousness knotting them into a restless tangle of scales and stress. “Y-you could wait for the human to reach A-Asgore. He’s absorbed the s-souls; he...”

As she trailed off, Sans’ eye sockets fell closed. “He probably fought them in other timelines. Either he forced them to reset, which would bring me back to life anyway, or he lost, in which case, I need to give them a fight that they hopefully haven’t already won. If nothing else, maybe I can at least tire them out a bit, soften them up enough that Asgore can prevent... this.”

His words turned Alphys’ train of thought from one screen to another, from the video feed of the murderous child’s present location to the records of their future and past.

Endless zigzags, some offscreen ones manifesting as vast backward leaps following long forward stretches, while the ones currently visibly jumped wildly back and forth in a space of minutes or seconds – the former a chain of unexplained resets, and the latter theorized to be the product of a time traveler’s repeated death.

And then, less than half an hour after their current point in time, it ended.

All of it.

A simple line on a chart that so inadequately symbolized the lives and hopes of everyone she knew, suddenly vanishing forever.

The soft sound of cardboard sliding against cardboard drew Alphys’ attention to her friend’s fuzzy mittens, and she watched in confusion as he carefully, almost reverently opened the present that had been protruding from his pocket ever since he entered the room.

He lifted the lid, and a tag swayed at the end of a short string, the name “Papyrus” flashing briefly into view before he slid the piece of cardboard into his other pocket.

Reaching into the box, he gently withdrew two small figures: a heavily armored blue fish, and an outlandishly dressed skeleton. The former sent a spear through Alphys’ racing heart, and Sans held the action figure carefully as he stepped toward her.

“Here.” Placing the small plastic Undyne in Alphys’ shaking claws, he slipped the miniature Papyrus into the right pocked of his hoodie. “To remind us what we’re fighting for.”

For a moment, Alphys stared mutely at the toy, the last tiny remnant of the woman she loved. Her heart seemed to wedge itself as a painful lump in her throat, and it took several tries and a few swallows to regain her voice.

“Thank you,” she whispered, raising eyes that glistened with tears toward... the place where Sans had been standing a second ago.

The place where he no longer was.

Her eyes snapped up to the human’s monitor, and her heart fell from her throat to plummet through her churning gut.

The child had entered the Last Corridor. Their small, innocuous, yet frighteningly powerful form was all but lost amid the size and splendor of the hall, but their fingers were wrapped firmly around the hilt of an old, worn dagger.

Eyes down, expression flat, they came to a halt, and Alphys’ pulse followed the human’s lead as her eyes found the source of their hesitation: an equally small, slumped figure, standing resolutely in their path.

“Heya. You’ve been busy, huh?”

Trembling claws tightened desperately around the plastic Undyne, and with her eyes fixed on the monitor, Alphys didn’t see the lurking form that poked up through the floor in the hall: a round, wary white face, surrounded by petals of sunny gold.

For a moment, the flower stared at the monitors, silently absorbing their grim report.

Then he slipped back into the ground, and vanished from sight.


It was amazing how much fear, hope and anxiety a simple plastic action figure could inspire.

As his fingers closed around the Papyrus in his hoodie’s pocket, Sans felt the pulse of his magic quicken. He’s counting on me. He doesn’t know it, but if I win… if I can get the human to reset... he’ll come back to life.

And if I lose…

His fingers clenched, as if holding on tighter could bring back the dead, or a fierce enough grasp could symbolically crush the threat that loomed over them. If I lose this fight, then I’ll have failed one of the few reasons I had to keep trying.

So, let’s see what I have to work with.

A few feet away from him, the human had shambled to a halt, their dead, eerie face fixed on him, but their nearly-closed eyes turned subtly toward the ground. Unable to meet his steady stare, and burned by an emotion carefully concealed by a wholly inadequate mask.

To anyone else, the guilt in their expression might have been invisible. To Sans, it was nearly a scream.

Whatever they’re feeling, it isn’t enough to stop them, but maybe I can work with it.

“So, I’ve got a question for ya.” The warrior in him wanted to keep an eye on the dagger, but his inner tactician insisted instead on seeking data in his opponent’s face. “Do you think even the worst person can change? That everyone can be a good person, if they just try?”

No answer came from their tightly-closed lips, but he could still see it: a subtle tension in their shoulders, a tightening in their jaw and in their grip on the weapon. Their guilt flared a little stronger, but there was something else... Reluctance? Uncertainty?



The expression was deeply unnerving, but Sans had had altogether too much practice in pretending to be all right when almost nothing was. The chuckle he forced from his chest sounded as natural as it was humorless and grim.

“Heh heh heh heh... all right. Well, here’s a better question. Do you wanna have a bad time? ’Cause if you take another step forward, you are REALLY not going to like what happens next.”

Now that was strange. They still weren’t answering him, but a flicker of dread crossed their face, as if…

A horrible chill went thundering down his back, like an avalanche of ice through his spine and chest. That expression... Do they already know what I’m capable of? Have they seen it before?

Have I already as good as lost this fight?

No... I can’t have already lost. They aren’t looking forward to this, I can tell.

But if that’s the case, then... why do they look like they’ve just found something they’ve been looking for for a long time?

The smile they were putting on their face was fake – he suspected that even Alphys would be able to see that. But amid all the guilt and regret, something inside them was vaguely… he couldn’t say ‘pleased’, but… relieved?

That isn’t the look of someone who’s happy about what’s happening, but... Is there something coming after this that they’re looking forward to? Something they really want, coming just after this fight?

Are they really just that happy about ending the world?

Welp… if they do step forward, I’ll just have to give them something to be unhappy about.

He hadn’t expected his words to deter them. And yet, as they took that defiant step toward him, he couldn’t help but feel... disappointed. Maybe even betrayed.

And now he would have to commit a betrayal of his own. “Welp. Sorry, old lady.”

The child’s smile faltered slightly, and their grip on the knife trembled. But even as the glowing gossamer lines of the battle box began to spread from Sans’ feet, his opponent didn’t back off, and he strongly suspected that they never would.

Maybe I can reach them in mid-battle. Maybe not. Either way...

“This is why I never make promises.”

I don’t think I can afford to hold back.


Even after all these timelines, it still felt strange to feel time shift backward without needing to die to make it happen.

Normally, there would be pain, and the feeling of his tiresome floral form dissolving around the hollow tangle of thoughts and half-felt emotions that should have been a soul.

Normally, there would be a feeling of falling, of drifting away from the world, and the knowledge that if the burning grasp of his artificially injected determination would just let go for an instant, he could finally be free of the lonely, exhausting swirl of gray that was the life of the soulless undead.

The first time he’d found himself unable to find a save point, the pulse of his magic had quickened with excitement. And the first time Frisk had reloaded a save, exploiting the power they’d stolen from him, the feeling had been glorious. The newness, the fresh cornucopia of unpredictability in a world long gone stale, had intoxicated him to the point of obsession.

But now, as the blinding flare of Sans’ blaster gave way to the lightless void of the Save Screen, and the Screen dissolved into the gray exterior of New Home, Flowey found himself unable to savor the novelty as he once had.

Now, his obsession was pointed elsewhere, and he needed to make sure that the being at the center of it stayed on track.

The human child was stumbling now, unable to make the rapid switch from the wild movements of combat to the motions they’d been performing when they last created a save point.

The transition from a frantic dash to a slow, resigned march hit them like an invisible hand, knocking the rhythm of their steps into an awkward stagger, and from his position in the front garden, Flowey heard them gasp quietly.

A small sigh slid from a body that shouldn’t have been able to produce one, and the flower briefly closed his eyes. “I told you.”

Frisk jolted, glancing at him like a dazed jaywalker noticing an oncoming car for the first time. “W-what?” they asked, their unsteady voice matching their gait as they stumbled to a halt. “You mean about Sans?”

Well, that too, but that part had been inevitable. This, on the other hand... “No. I told you not to save while you were in mid-step. One of these times, you’re going to fall on your face.”

“Oh. ...Sorry.” Their eyes turned away, their soft face etched with the ever-present guilt that they couldn’t seem to shake no matter how hard they tried to mask it.

Flowey wished they were a better actor. As much as he’d never thought he’d think this, there were days when being soulless was an asset.

At least he didn’t have to feel the devastating impact of the line that had just been crossed. He didn’t have any feelings of guilt or loss to mask.

Surely there had to be some way for Frisk to-

“But it helps, doesn’t it?”

The soft, questioning voice drew his mind from his machinations, and Flowey frowned at them. “What do you mean?”

“Well… You told me that to deal with strong opponents, I needed to adapt to sudden changes and never lose my balance, even if I’m surprised. So, isn’t this just more practice?”

“Heh.” Flowey smiled, ducking his head slightly in acknowledgment. “I guess it’s better if you think of it that way. But anyway, you’d better get going. You’ve got lasers to dodge.”

As expected, the reminder of what was coming drew Frisk’s mouth into a hard, flat line, resignation seeming to age their features a decade within a few seconds. Their fingers tightened around the frying pan they’d been holding when they saved, and their short legs moved as if they were wading against an invisible tide.

The sight was truly pitiful, and Flowey knew that if he could still feel compassion, he’d be absolutely miserable right now.

Instead, there was simply emptiness, and a purely intellectual hope that his playmate-turned-weapon wouldn’t break before the job was done.

Hold on, Frisk. We’re almost there. Just a little longer, and this nightmare will be over.


“Is that the flower you were talking about?”

As the child on the monitor glanced toward the talking plant, Alphys nodded miserably, her head staying a bit too low as the gesture ended. The guilt that pressed her face floorward was almost tangible, and her claws twisted miserably around each other, like short snakes trying to grind each other out of existence in a wave of self-loathing.

It was hard to muster the energy to comfort her, and for a moment, Sans considered just walking away. Whatever he did right now, it wouldn’t matter for long; the timeline chart that lit the room made that all too clear.

In a few minutes, this encounter would be erased from memory, struck from reality by the backward time leap of a human who just wouldn’t stay dead. Like every other conversation, every event, every task completed and step of progress made, this meant less than nothing in the long run.

But the present moment still existed, and the fact that he existed too meant he was going to do something. That something could be to walk away, to simply stay silent, or…

Heck with it. If something was going to happen in this moment no matter what he did, he might as well use what little power he still had to make it something good.

The grip of his hand on Alphys’ shoulder felt painfully inadequate, a sad replacement for the people whose likenesses lay in a box in his pocket. But as she looked at him with big, liquid eyes, unshed tears flaring in the screen’s relentless death-white light, he was glad that he’d made at least this token effort to comfort her.

“You couldn’t have known.”

Her face fell again, and he knew that the consolation rang hollow. What happens when something without a SOUL gains the will to live?

He’d seen the lab notes, and silently shaken his head at the recklessness of giving consciousness to such an empty being. And yet, could he blame her? She had done too much, and often he felt like he had done too little.

There was a dark side to both determination and patience, it seemed.

But maybe not as dark as he’d thought. “Papyrus mentioned it, you know.”

There it was again, that quick, startled glance, but this time the gratitude was overwhelmed by the surprise. “W-what?”

“He told me he talked to the flower. Apparently it likes him, and it told him to get out of Snowdin before the human arrived. Heh...”

The one-syllable chuckle fell from his mouth, fondness and admiration filling the space where humor should have been. “Trust my brother to win over something that shouldn’t be capable of being won over. If he’d just been able to do that with the human...”

A sigh fell from an empty ribcage as he shook his lowered head. “Well… I guess it doesn’t matter now. For all we know, the flower’s behind this whole mess, and my bro being the sole survivor is just one of the outcomes it hasn’t seen yet. Either way, I guess it’s time to see if I can bring him back.”

Alphys jaw clenched tighter, and even as he turned away, Sans knew what she was thinking.

The battle had barely begun, and unless the readings were wrong, neither of them was going to like the way it was destined to end.

“A-are you sure you w-want to do this?”

Sans paused, his head bowing further, and it took an effort to make himself look at the timeline chart again.

Judging by the red on the line that marked the human’s progress…

“I think I already did.”


What does it feel like?

As he materialized in the Last Corridor for the third time, Sans stared at his opponent in silent, disturbed fascination, his observant gaze probing the slopes of shadow and light that shaped the young, stony face.

The lines on the timeline chart implied that the human’s second attempt on his life had lasted longer than the first, but only by a few seconds. They probably hadn’t even survived his opening move, yet their body language showed no sign that they intended to give up.

Does the human soul not feel pain the way monsters’ do? Do my attacks just not hurt them? Are they going through this numb?

If they DO still feel this… if it does still hurt… then why?

What do they want that could possibly be worth that?

They’d come to a halt, and were staring at him expectantly, as if waiting for him to engage them in combat… or to provide a line of dialogue that they hadn’t heard before. A scrap of the unknown that was somehow worth killing for.

Is their sense of curiosity really just that powerful? They don’t LOOK curious, but if that isn’t their motivation, what is?

And, more importantly, how many tries will it take before they finally give up?

Only one way to find out.

Looking the human in the eye, he forced his grin not to falter. “Hmm. That expression… that’s the expression of someone who's died twice in a row.”

Heh… as if I would remember what your expression looked like after you died and went back in time. But it’s a good setup for some jokes. A face-reader and a face that makes no sense walked into a corridor...

“Suffice it to say, you look really… unsatisfied. All right. How ‘bout we make it a third?”

I really wish your face looked more unhappy about that idea. And I wish I knew why, despite everything, it bothers me more than it seems to bother you.


They’re getting better.

All but a sliver of the human’s HP bar was tainted with livid, venomous purple, Karmic Retribution coursing through their soul in the wake of Sans’ attack. Their feet were braced wide beneath them, and their short fingers clutched their knees as they recovered from the exertion and pain.

With every passing moment, a bit of their life force drained away, an inexorable fading that moved far too slowly for the skeleton’s peace of mind. The damage his opponent had taken was a testament to the fact that he was still better at his job than they were at theirs, but… it wasn’t enough.

They’d predicted his blasters with disturbing accuracy, changing directions and running to each new safe zone even as the streams of roaring light faded from the air, and only the sheer size of his final set of cannons had enabled him to score a hit.

Three tries, and they’d memorized his best attack well enough to survive it.

But at least they hadn’t survived it by much. Their Level of Violence had been stalled at an inexplicable two in Waterfall, and while the intervening battles had raised it somewhat, their thirty-six HP still withered quickly under fire.

Their legs quivered as they straightened up, but that was a blip in Sans’ radar compared to the uncontrollable trembling in their hands as they released their grip on their knees. The child’s breath was quick and shallow, struggling far more than his brief assault should have caused, and every cell in their body seemed taut with hesitation.

Their eyes lifted from the ground at their feet, only to land on the floor beside his slippers, as if they knew they should look toward their opponent but couldn’t bear the sight of him. One of their cheeks pulled inward slightly, caught in the straining vice of their teeth.

Twenty-five, twenty-four, twenty-three. Their HP was still draining, but even as their life force bled away, the child hesitated, their knuckles whitening with their grip on a dagger that they seemed to be in no hurry to use.

Aren’t you gonna take your turn, kid? The suspense is killing someone, and it isn’t me.

Something moved in the corner of Sans’ vision, but before his eye sockets could capture it, the motion was gone.

A subtle shadow. A hint of yellow. Flowers are blooming, indeed. I hope this isn’t a setup for a sneak attack.

Masking his awareness of the observer, Sans pretended to focus on speaking to his opponent. “Huh,” he commented, his falsely carefree voice echoing faintly in the eerie silence that the roar of his attack had left behind. “Always wondered why people never use their strongest attack first.”

And now I wonder if you will.

His back prickled with the suspicion that something was moving behind him again, but even as he split off a bit of his focus to watch for a backstab, the majority of his attention was recaptured by a far more significant movement.

The human was finally charging at him.

Their steps were rushed and uneven, and their feet flew beneath them in a haphazard flurry, as if their legs had disconnected from their body and were blindly attempting to close the distance without regard for anything else.

Those small, short fingers tightened around the dagger, and Sans tensed as he recognized his attacker’s posture from an earlier fight.

Heh. As if that brutal and undeserved execution could be called a fight.

Sure enough, there it came: a sharp horizontal swing, aimed for the vulnerable column of his neck. Just like the blow that killed Papyrus.

Anger flared through Sans’ body, masked by the perpetual grin on his face and coupled with a bitter hint of derision as he easily sidestepped the assault.

It was strange, that such a prolific killer would make such a sad excuse for a murder attempt. A large, obvious movement, and embarrassingly predictable… except that the final instant of it wasn’t.

As the child stumbled to a halt and the battle box re-closed around them, Sans felt his eye sockets widen slightly in his closest equivalent to an eyebrow raise.

That attack… wasn’t aimed the way I thought it would be.

Quickly masking his surprise, Sans winked at his opponent, raising his stubby arms in a shrug. “What? You think I’m just gonna stand there and take it?”

Their glance turned down and away, as if pushed by the frown that weighed on their forehead. The familiar feeling of tense suspicion flared between Sans’ ribs; they didn’t look as surprised by the dodge as they should have been.

No… I don’t think they thought that. Which means they’ve tried to kill me before, or been told stories by someone who has.

I knew that flower was trouble.

That was a problem for another time, if such a thing existed. For now, he had more important questions to ask. “Y’know, kid, when it comes to using your strongest attack first… I can’t help but notice that you didn’t. Maybe you were trying to, but at the last instant… you almost pulled that punch, didn’t you?”

As he’d hoped, the question struck a nerve. Every inch of their body tensed, and a dark tide of something almost like dread washed across their face.

Ha. I know something you don’t want me to know.

“Heh… guilty conscience, buddy? Havin’ a hard time taking a swing at me? Actually, that wouldn’t really surprise me. There’s been something bugging me ever since you first walked out of the Ruins. Something that shouldn’t be possible.

“You act like you’re the worst person you can possibly be. Killing everyone you come across. Trying to come across more of them, so you have more people to kill. Killing the people who might have been your friends, if you’d given them a chance.”

The child was shaking by now, teeth gritted and knuckles pale as their fingers clung to the dagger, as if its weight had multiplied tenfold and anything less than their most desperate grip would let it fall from a hand that didn’t want it.

Come on, kid. Just let go.

“And yet,” he continued, keeping his tone casual and curious, “you actually might not be the worst person you can be, even though that shouldn’t be possible. I have to admit, I’ve never seen anything like this.

“Come on, kid – you’ve gotta let me in on your secret. How is it that a person can have the execution points of a level nineteen, and yet only be at Level of Violence five?”

A mask of stone snapped into place, laced with cracks that shone with pain, but deliberately blank enough to make him think he was getting closer.

Whether that was closer to getting through to them or to making them shut him out entirely, he wouldn’t know until he tried.

“You’re not happy about this, are you? Even though you’ve killed so many people, you never completely distanced yourself. Even though you should be numb by now, you’re still feeling it.”

So many expressions on one face. Fear. Misery. Dread. Relief.

All of it nearly drowned out by pain, pain, pain.

Could a choice that hurt them that intensely really have been their own?

“Whatever led you down this path... was it really your decision? Or is there something pushin’ ya... something you can possibly solve another way?”

With that, the mask closed entirely, the cracks sealed by the shadow that fell across their face. “There is no other solution.”

Even as their grim, resigned voice faded from the air, Sans couldn’t help but wonder if an unspoken phrase lingered in its wake: “I should know. I tried.”

I certainly hope you did.

He’d used his turn on talking, and now they were charging at him again. This time, the last-instant waver was absent, and the vicious swing came closer to carving a new opening in his hood.

“Welp... too bad then,” Sans commented, his slippered feet sliding to a halt on the smooth tile floor. “I mean, too bad for YOU. Whatever you’re hoping to accomplish with this... I hope it’s better than what you’ve given up.”