someday, you gotta learn when to quit (and that day's today)
An Undertale Multi-Crossover Fic

Notes: This one-shot is set at the end of Undertale's Genocide Route, with some elements pulled from coincidencless' fic, Megalomania. This fic is based off a… particular cover of Megalovania made by Man on the Internet.

You know what I'm talking about.

[Chara]

New Home
Final Corridor

"heya. you've been busy, huh?"

And there he was.

I walked into the Judgment Hall, laying my crimson eyes at the skeleton standing solemnly in front of them.

I couldn't help but smile at the sight. Finally. This bonehead's gonna get what's coming to him.

It's been a long road to this moment. Nineteen Levels of Violence, gained from massacring any monster that dared to stand in my way. Tearing apart the world that was once my home, all to show them the true meaning of this world.

Perhaps, in another timeline, I would've tried for a different route. Being pacifistic, showing compassion, stuff like that.

But now I know better than to try.

Asriel was wrong. You can't get anywhere with MERCY.

In this world, the only way to get what you want… is to FIGHT.

And now, I've got one last target left before I can complete my mission.

My mission to eradicate this wretched world, devoid of anything resembling hope or happiness.

Sans.

* SANS – ATK 1 DEF 1
* The easiest enemy.
* Can only do 1 damage.

This is going to be easy.

"so, i've got a question for ya."

He closed his eyelids.

"do you think even the worst person can change…? that everyone can be a good person, if they just try?"

I snorted, stepping forward.

Of course not. There's no such thing as 'a good person' in this world.

Who does he think he is, asking that question?

He's not any better than me, after all.

"heh heh heh heh… all right. well, here's a better question."

He opened his eyes—and extinguished the lights in his sockets.

"do you wanna have a bad time? 'cause if you take another step forward… you are REALLY not going to like what happens next."

I stepped forward again. As if you could do anything to me.

I survived Undyne the Undying.

I destroyed Mettaton NEO without blinking.

You're just a lazy skeleton. You didn't even try to stop me before.

What makes you think you can do so now?

He sighed.

"welp. sorry, old lady. this is why i never make promises."

Wind blew through the corridor.

Silence floated about in the atmosphere.

It was just him and me, here in the grand finale.

And yet, instead of becoming any sort of serious…

Sans, almost whimsically, started to sing then and there.

"You know, I've been thinking about you and me…"

I twirled my knife in my hand as I waltzed on.

"Was this preordained? Was this meant to be?"

My leisurely waltz became a full-on dash.

"Somewhere deep down, I thought that you could change…"

This is it, Sans! It's the end of the road! I grinned.

Let's see how fast you'll die before my hand!

"Let's cut to the chase—
Matt from Wii Sports gonna punch you in the face!"

…

I stopped.

That… didn't come from Sans.

I'm sorry, what?

Just then, I felt something slam into me from behind—

—and everything proceeded to go horribly, horribly wrong.

Chaos erupted through these so-called sacred halls.

I have no idea what's going on, or how any of this is even possible.

All I know is…

"Prepare yourself, fallen child! Matt from Wii Sports is gonna break your will!"

…I am not having a very good time.

* MATT – ATK 1649 DEF 155
* Who the hell is this guy!?
* He's not a monster, so where did he—!?

I narrowly dodged 'Matt's' superpowered punch as he barreled toward me. I learned the hard way that he's strong enough to potentially shatter my SOUL in only a few blows—I can't afford to get hit by him again.

If that was everything I had to deal with—this freak and Sans—I'd hedge my bets on being able to outlast them.

Unfortunately…

…that wasn't the case.

Bones white and blue scattered themselves around the battlefield, keeping me even more on my feet. I grit my teeth and locked eyes with their source—

"NYEH HEH HEH!"

* PAPYRUS – ATK 20 DEF 20
* How is he still alive!?
* I ground his skull into dust!

"I STILL BELIEVE IN YOU, YOU KNOW!" that annoyingly high-pitched skeleton shouted from beside his (noticeably more upbeat) brother. "YOU DON'T HAVE TO BE SO VIOLENT! BUT UNTIL THEN, I, PAPYRUS, WILL HAVE TO STAND IN YOUR WAY!"

Shut up, shut up, shut up…!

"And he's-a not the only one!"

A circle of blue bones abruptly surrounded me, stopping me right in my tracks. I had scarcely any time to think of a way out when I was double-teamed with a literal lightning uppercut and hammer-made haymaker.

AGH!

I went flying into the air, slamming into the ceiling a few feet away. Landing unceremoniously on the floor, I crawled back onto my feet and ate a Legendary Hero—40 HP is not enough for this, I internally growled.

Two figures—one lean and green, the other stout and imperial—stood where I previously was. It was clear that the two of them, despite their vastly different body types, knew how to coordinate with each other.

* LUIGI – ATK 281 DEF 242
* The Green Thunder, or so he says.
* Way too strong for a normal human!

* KING DEDEDE – ATK 333 DEF 315
* Says he's gonna give me a clobbering.
* I'm not inclined to disbelieve him!

"I've seen a lotta demons in my time—but you've gotta be one of the worst!" King Dedede spat, seconds away from losing his cool and going all feral on me. "At least the Haltmann Works Company didn't go so far as to kill people!"

"I can see it in your eyes," Luigi hissed—he looked so scrawny, and yet he was just as intimidating as everyone else here. "You'd-a kill Mario, the same way you killed Papyrus without regret. Well, no more! We'll make this your last blunder, dirty brother killer!"

The duo charged on forward, each with their respective mallets to watch out for. I hopped backwards and away from their grasp—and was promptly ambushed by a flurry arrows cutting into my skin.

"Ha! Got 'em! Not so tough when you're dealing with more than one guy, huh?"

I whirled around to see a crowd of teenagers in the back of the corridor, led by a guy clad in black and yellow. Medieval bows and arrows were in their hands, their leader packing a particularly strong-looking one.

* CLAUDE VON RIEGAN – ATK 45 DEF 31
* He brought even more reinforcements!?
* This hallway is crowded enough as it is!

"A part of me wonders why you'd want to be so cruel, killing everyone you see…" He cast a grin at me. "Well, s'pose it doesn't matter. Golden Deer, get ready to keep firing!"

"Yeah! FEAR THE DEER!"

I ducked beneath the newly-shot projectiles and made a mad dash to the skeletons in desperation. They were the weakest links; if I could take them down first, that'd make the rest of this fight easier!

I… made it exactly five meters before I got crushed by a weight from above.

"You can't hope to face my power," a predatory voice sang in glee, "for this is my finest hour!"

A chant from just outside the hallway's walls echoed into my ears.

"Hail to the king, to the king of the Kremlings! Hail to the king, to the king of the Kremlings!"

* KING K. ROOL – ATK 224 DEF 198
* Allegedly the 'King of the Kremling Krew'.
* Is that a belly made of gold!?

"Hail to the king, to the might of which we sing!"

He was a massive human-like crocodile, wearing a small crown and a flowing red cape and two jaws fit to bite my arm off. I struggled to get him off of me, thrashing as wildly as Frisk's body could—

—and then purple smoke was blasted into my face, making me scream in pain.

King K. Rool promptly jumped off of me and whacked me with a boxing glove, the potted plant next to him snapping its mouth in delight.

* PIRANHA PLANT – ATK 146 DEF 138
* It's… a plant. A freaking plant.
* Why!?

"MWAHAHAHAHAHAHA!" he laughed manically—no fair, it should be me who gets to do that! "Ordinarily, I wouldn't be here fighting you—but it wouldn't do to have someone eviler than I upstaging me! Isn't that right, 'lil Piranha?"

That irritating weed stuck his tongue out, lapping up all the praise.

He's just like Flowey… ugh…

I stumbled upright once more, trying not to collapse from the poison coursing through my veins.

"That's one thing we can both agree on, hah hah hah!"

Some crazy white-haired wackjob entered the scene next, accompanied by… agh…!

* GOLISOPOD – ATK 125 DEF 140
* And this one's a bug! A humongous bug!
* EW!

"There ain't anyone more wicked than me and him, punk!" the jacket-wearing delinquent declared, mismatched glasses shining atop his forehead. "You're pretty stupid, if you think you can match up to big bad Guzma!"

"M… M… Match up… to… this…!" I heaved, lurching back into the fray. His malformed insect was quicker on the draw, though—it literally warped to me and clawed me silly.

And if that wasn't enough…

"Take this!"

…someone burst from the ground and socked me hard in the jaw, a huge gloved hand throwing me into a column at what felt like the speed of sound.

"If you keep going on this path, then we'll have to be the ones to set your heart free true," a red… echidna(?) said, slamming his fists together with a resolute expression. He brought out a giant glowing emerald and let it pulsate brightly. "Cleanse it of the evil spirit that's in you!"

* KNUCKLES – ATK 311 DEF 194
* Rougher than the rest of them.
* Would rather not hear him chuckle.

I bit into another Legendary Hero and let its healing energy wash over me. Then, I took stock of my current situation.

On one end, Claude von Riegan and his band of idiots are ready to potshot me when I'm least expecting it. On the other, Sans and Papyrus are sending out bones from the walls and the floor; one wrong move, and I'll be skewered from them. Matt, Greenie, and Dedede won't hesitate to give me hell for all I've done – and neither will the band of so-called 'heroes' in front of me.

That's just fine. Totally fine!

They may have me outnumbered… but that doesn't mean they're invincible!

I engaged the four in combat again, determined to bring them down come what may. Rocks and cannonballs and water projectiles were lobbed my way, and while I was taking a few hits due to my experience with them, that didn't matter!

I could do this! I could do this!

I was DETERMINED to see this through, even as I grow evermore exhausted—!

A Gaster Blaster spawned above me, charging up another blast of energy. Before I could even try to move my feet, it opened his mouth and unleashed its attack—

SNIKT!

KA-BLAM!

—and my SOUL shattered into pieces.

Darkness greeted me, as I had rapidly grown accustomed to.

Luckily for me, it didn't take long before my vision cleared up again.

I found myself back at the entrance to that accursed Judgment Hall, right where that familiar SAVE Point rested. I turned right and stomped through the corridor—

—and lo and behold, there was Sans and his disparate allies standing in the light, smug faces directed at my failures.

I glared daggers into that hateful skeleton's eyes.

* SANS – ATK 1 DEF 1
* …you little cheater…

"How… How did you—!?"

He chuckled and shrugged. His clear amusement at my situation made me want to slit his throat.

"well, let's just say that somebody else noticed how you were smashing up everyone and decided to lend me a hand. pretty masterful, amirite?"

"NYEH HEH HEH! INDEED, BROTHER!" Papyrus squinted. "…DID YOU MAKE ANOTHER PUN JUST NOW, OR—?"

My fists shook in frustration.

I… I can't lose to this… this horde of buffoons…!

I was so close… so close to winning…!

I refuse to let it all be taken away from me now!

"You refuse to-a stop, even after that…?" Luigi said, arms crossed… crossly. (That'll work.) "No wonder Master Hand warned us about your whole 'determination' schtick."

"Just as stubborn as Kirby, I see," King Dedede huffed—"they're only lacking the whole 'friendship is magic' thing he likes so much." He coughed into his arm. "Chara, was it…? You can still turn back from this, y'know. You may be at the moment a villain as vile as Dark Matter, but that doesn't mean I'm not willing to give you a second chance."

"Maybe it's naïve of us to try that," Knuckles admitted, "but heck, even Eggman has a good side—so it's worth a shot."

"Keep hopin' for a KO, though… and Matt from Wii Sports is gonna have to give you a badder time!" Matt exclaimed, punching the air in front of him.

"it's your choice, kid," Sans said, hands in his hoodie pockets as if the last thirty minutes hadn't happened at all. "there's the glimmer of a good person inside of you, somewhere. a person who, in another time, might have even been… a friend." He closed his eyes and waited for a response. "what do you say, kid? wanna lay your weapon down and just… forget about this?"

* Sans is sparing you.

…

…

…

Do they… really believe… I'm that foolish…?

Do they…?

…

…

Ha ha ha. Ha ha ha ha ha.

"Ha ha ha ha ha… HA HA HA HA HA HA HA HA!" I laughed and laughed and laughed, clutching my palm to my forehead in hysteria. The others were visibly taken aback, looking at one another in concern (as if). "I haven't come this far, just to give up now! I'm the first Fallen Child—former daughter of Toriel and Asgore! I'm the Demon That Comes When You Call Their Name!

"I'm Chara Dreemurr, the angel of destruction! And I will destroy this entire world, no matter how long it'll take!

"You wanna get in my way? JUST TRY AND STOP ME!"

Silence billowed through the corridor. I relished in the shocked and horrified expressions on everyone's faces, as if I could be anyone other than a heartless demon.

Sans breathed in… and breathed out.

"heh heh heh… so. you just wanna see this end, huh?" he said. "see how far you can descend, even if it means never making amends?

"…fine, then."

He opened his eyelids—and revealed a single iris flashing yellow and blue.

"looks like we can't afford not to care anymore."

The lights went out, and darkness filled the halls. I jolted despite myself, and involuntarily stepped back.

Then, one by one… a blue glow illuminated the members of Sans' party—and I couldn't help but freak out a bit from the sight of them.

Bones were spread out as far as the eye can see, accompanied by Gaster Blasters dangerously hovering through the air. Sans and Papyrus stood in the center, fire streaming out from a single socket each.

"I CAN'T SAY I'M NOT DISAPPOINTED THAT YOU'RE DOING A VIOLENCE—BUT OH WELL! PREPARE FOR OUR REALLY COOL ATTACKS!"

"You're gonna be sorry you chose the path of genocide!" King Dedede vowed, metal mask on his face and mechanized hammer promising pain a plenty. "We're gonna clobber you 'til you're seeing stars!"

From within a robot shaped like his head, Luigi pointed at me with absolute fury. "Take it from me, kid—it's time we stopped this child's play! It's time you learned to stop, learned today is the DAY OF LUIGI!"

Claude von Riegan, Piranha Plant, Guzma, Matt—their groups formed a half-circle behind the skeleton brothers, pounding their fists together in anticipation.

"Failnaught's gonna beat you blue and black 'til everything ends!"

"We're gonna beat you down and beat you down and never let up!"

"MATT FROM WII SPORTS IS GONNA BRING THE PAIN!"

And finally, there was Knuckles and K. Rool, standing atop the big emerald I had seen prior—the former pink and radiating power, the latter dressed up on an off-kilter pirate costume.

"Our duty is to save the light from evil deterioration…"

"…so that we of the Kremling Krew can pilfer it for ourselves!"

Over a dozen faces glared straight into my soul, sending all the shivers down my spine. The vitriol in their eyes was unmistakable—and for a moment, I desperately wished that they were turning that attention to anyone else.

Looks like I'm getting what I wanted… I gulped as they all cried out in unison.

This tale's gonna end, here and now.

"You are never gonna smile! You are heartless, you are vile!

"Say your prayers, fallen child…"

I felt my sins crawling on my back.

"GUESS WE'RE DOING THIS THE HARD WAY!"

Somewhere, deep within the depths of a stolen body, a little soul smiled.

"Go get 'em, guys."

You know I had to.

'Tis a month later than I wanted it to be, since I was busy putting up so many other fics, but—hey! It's here now.

Let's give out an F for Chara, y'all.

[F].