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English
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Published:
2026-02-23
Updated:
2026-05-02
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15,492
Chapters:
8/?
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Undertaker

Summary:

A child falls into the underground.

Chapter 1: Fallen

Chapter Text

(So, this is a Helltaker x Undertale Fanfic. Helltaker is a game about demon harems, BUTTTT we're not focusing on THAT part! We're focusing on the extra chapter and it's contents, Examtaker where you're a test subject for a science demon, so no harems today, we're focusing on THE UNDERGROUND. ANYWAY.)

MT. EBOTT
203X

A child stands over the entrance to the Underground.
"So, this is what the stories about. Let's see."

She jumps down.
Unlike what the legends told, after a rocky fall instead of flowers at the bottom... there's barely anything!
THUD!

She looks around the room she landed in, head bleeding. Instead of being an empty room it's clean, sterile and her blood is all over it.
"What..?"
She gets up and look around before entering the next room, a giant screen sits there on the wall, an empty flower pot sitting in the centre of the room.
"What..."
They murmur before the screen on the wall flickers to life.

Red goggles, white horns, white hair.
Lab coat over a black and red suit.

Loremaster, The Science Demon appears.
"HELLO! Ooh, you're hurt? Fun!"

 

The child yelps.
"WHAT THE HELL!? WHO ARE YOU?!"

The demon looks at the kid.
"My name's Loremaster. Pleasure to meet ya. Let me get you registered in my database, so I'm assuming you're..."

The kid responds, confused.
"I... I don't know."

She hesitates.
"Pardon?"

The kid grabs her head.
"I-I-I... what the fuck? What is my- what- huh?! Who am-"

The science demon blinks.
"I see, well anyway."
She types on a tablet.
"Strange little fellow... noting... amnesia..."

A vial stabs into her hand from behind.
"OW, WHAT THE FUCK?"

The demon looks up.
"Just gathering biometrics, silly!"
Database updated.

"That's a funny name, anyway. I shall proclaim you Project 64! Have fun."
The screen turns blank.

A metal 'stem' spikes out of the ground, and the end that faces towards Frisk opens and out pops four pieces of metal, it then unfolding into a face with petals, a screen coming forward, then lighting up, sound emanating from the speakers in the pot.
"I'm Flowey! Flowey the Flower!"

The fallen child looks at the metal flower.
"Wow... umm... strange! What are you doing here..? I...I thought things like you were... organic."

The flower looks at her.
"The old was replaced with the new. I no longer need photosynthesis to survive. Unlike the old model."

She steps back.
"O-old model? That scientist replaced organic life with that?"
She looks at 'Flowey' in horror and fear.
"What the hell... what is this place?"

The pot grows wheels as the mechanical flower rolls towards them.
"We were upgraded, kid! Everything's better than it used to be! No more hassle, we're safer this way."

They stare at the mechanical plant.
"You... you are- I- I- Wh... I'm scared..."

The screen shows a horrendous melting face.
"You should be. In this world, it's kill or be killed."

The kid screams.
"AAGH! WHAT THE HELL!"
Buzzsaws on metal sticks shoot out of the metal pot and try to tear the kid to pieces.

Cheerful, entertained giggles are heard from the screen, Loremaster totally forgot to mute her mic.
"Hehe, this kid's really getting wrecked!"

The kid shouts at her.
"I CAN HEAR YOU!"
The science demon looks at her mic button.
"Oh shit."
A beep can be heard, she muted her mic but is probably still laughing at the kid.

The child dives to the metal ground, landing on her stomach.
"Ackhaha... damn it. AAH!"
She crawls back as a buzzsaw nearly takes her head off.
"I-"
Bzzzzzzzz.
"AA-"
She's trying to survive this hellish onslaught of saws when...
Flowey's face opens and she shouts.
"WHAT THE FUCK-"
It's a cannon.
The kid grabs the metal head and tries to rip it off to no avail.
"Damn it- WH-"

Slice.
A buzzsaw lands a clean cut on the kid, luckily for them it was a surface wound, tis but a scratch.
"ACK! SHIT! DAMN IT!"
She curses, holding her arm to the wound as the mecha-Flowey wheels towards her.
"AH!"

She kicks at it... knocking it over... it can't get up.
"Wha..."
...
She stomps on the robot flower, extinguishing it.
"That was weirdly anticlimactic. Anyway!"
She progresses past the room and sees what happened to the RUINS.
Mechanical, lost all flavour.

 

She holds both of her hands closed to her chest and on the ground she finds something.
A small metal rod, deciding she could use it to defend herself, she picked it up.

You picked up a metal rod.
ATK +2

"Hmm."
She lightly hits it against her hand.
"Seems sturdy enough."
She looks in her pockets and finds her phone.
"Maybe this'll help me remember my na..."
It's broken.
"Fuck."
She tries in vain to turn it on.
"Hm..."
She spots the loudspeaker.
"HEY, LADY!"

Loremaster's voice appears.
"Hehe, you think I'll fix your phone. I like you being in the dark, 64."
Beep.
End of transmission.

"..."
She flips off the camera in the top corner off.
"Fuck you, bitch."

The scientist's voice comes back on.
"I can send more mechanised monsters to your location, kid. Don't test me."

The child looks.
"Just tell me my name already."

Radio silence.
"No. Not even I know, but you're Subject 64 now! So... better get used to it!"

She looks at her, upset.
"I'm not gonna use that name! I'm- uhh..."

A giggle is heard over the loudspeaker.
"This is entertaining for me, 64. Will be in touch!"

The fallen child enters the next room.
"I don't even remember why I'm down here... I'm so scared."
She sniffles.
The girl progresses through the Mechanised Ruins, seeing the sterile environment makes her really feel like a fucking lab rat, it makes her hands shake.
"O-oh god..."
She takes a deep breath and presses on, being a 'big girl' in her muttered words.

"I can do this... I'll escape... wherever I am and I'll... go back... home? Where is home? Who-who am I?"
She shakes her head and presses on and enters a room lined with spikes and buzzsaws.
"O-oh, okay."
She hops through the labyrinth and lands on the other side, landing with only a few scratches.

"Oof..."
The girl peeks up and looks around, deciding to continue walking through the Mechanised Ruins, still holding her chest wound.
"Ooh..."
She spots a roll of discarded bandages.
"Okay..."
She lifts her jumper up to where the wound is, her lower stomach and wraps the bandages around it.
"Okay..."
She lowers the jumper back over her waist and continues through the mechanised ruins, coming up to a run down house, seemingly the only organic thing in this soulless metal hell.
She sees some moss on the floor.
"I wonder..."
She eats the moss.
"Mmmm... yum."
The fallen girl enters the house, seeing cobwebs everywhere.
"The hell happened here?"
She shouts out.
"Hello? Anyone?"

But nobody came.
"Oh..."
She grips the fabric of her jumper, slightly hyperventilating.
"Am I really...alone?"
She feels her legs shake as everything else beings to feel heavy.
"Mr...uh... nonononono..."

She looks around and enters the kitchen, hunger still pounding against her stomach.
She opens the fridge and sees a pie, totally stale, but seemingly safe to eat.
"Mrm..."
She takes a big bite out of it, it was incredibly hard, but tasted decent enough.
"Mrh..."
She heads down the staircase and standing right before the exit to the RUINS.

Mecha-Froggit.

The girl puts her hands over the metal rod.
"I-I'm not afraid."
She is.

 

Loremaster appears on the screen again.
"Okay, Subject 64. Now for your first real test, can you fight back against Subject 020."
Loremaster forgets to mute her mic again when turning the screen off.
"LUCI WHERE'S MY BANANA BREAD."

The child shouts again.
"FORGOT TO MUTE AGAIN."

The science demon shouts back.
"SHUT IT!"
Beep.

The robo-frog's metallic tongue shoots out at the child, lashing around like a whip, the fallen girl blocking with the metal rod.
"Ok-okay, uh, it's a uh... really blunt object so... blunt force trauma... how can I remember what that is but not my own name- AH!"

The tongue bats her across the room, making her land face first into the wall.

"Oww..."
A bullet shoots out of the Froggit's eye, nearly killing her right then and there.
"EEP!"
She picks up the metal rod and runs towards the Mecha-Froggit before jamming the rod into its head, making the thing spark out of life.

"I-I-"
She breathes heavily.
"I-"

Loremaster's voice appears again.
"Now, you're already proving promising... haha."
End of transmission.

The girl looks to the exit to the RUINS.
She opens the door and exits.

U N D E R T A K E R.