[NOTE: GRAHHHHHHHHHHHH!!!!! THIS PLAYLIST IS OUTDATED GRAHHHHH!!!]
I will NO LONGER be updating this playlist, as I have a different, more organized way of sorting AUs!
Please check out my NEW Masterlist below!
https://soundcloud.com/brandoneatsair/sets/masterlist-hub

My UNDERTALE AU Masterlist!
For every UNDERTALE AU I can find on SoundCloud.

Contains COMPLETE, INCOMPLETE, and ONGOING AUs.
We've reached the maximum with 500 tracks! (If some don't get removed)

DISCLAIMER:

Inform me if:
- You want an AU removed.
- An AU isn't in the playlist.

"Once Upon A Time" replacements / equivalents are used.
If there isn't one, the "earliest" track will be used.

I will be using ONE version of a track per AU.
Older / outdated versions will NOT be used.

Organization may be inaccurate. Inform me if I messed up!
Anything below COOL TALE is still unsorted!
(Trying to sort everything by naming convention / alphabetically!)

:ORGANIZATION:

UNDERTALE - Base OST - UNDERTALE
"Remix" - Reworked Base OST - UT: Alternate --> Swapped Rhythms: Advanced Reboot
"Sequel/Prequel" AUs - Sequel/Prequel to UT - STARCHILD --> DONTFORGET
"Personality" - Alters Story - underfellproject --> Fallen Kingdom
"Divergence" - Alters Characters - UT: Halloween Hack --> gone.ogg
"Swap" - Alters Roles - Bob Lion: UNDERSWAP --> NEGATIVESHIFT
"Combined" - Alters All of the Above - UTY: Halloween Hack --> FALLEN STARS
"Broken" - Wrong/Merged AUs - An Ordinary UNDERTALE Mod --> Help_Tale
"Megalo" - Megalo's take character roles - Recognized Maniacs --> Existential Oddities: Doom Island
"Crossover" - NON-UT - MOTHER: Bound Underground --> WYCCC!
"Self-Insert" - AU creators / OCs - Sewerstory --> Genericophony
"Multiverse" - Various NON-UT (+ AU creators / OC') - Tale of the Chilled --> INTERWOVEN
"Joke" - Joke / Non-serious AU - Stroyshift --> COOL TALE

UNDERTALE by Toby Fox
AUs/Tracks by respective creators
Cover art by me
Also check out my Deltarune Masterlist: https://soundcloud.com/brandoneatsair/sets/deltarune-au-masterlist

[OUTDATED] UNDERTALE AU Masterlist

Here are some Au themes I found when exploring the SoundCloud website. Enjoy.                                   
Rules for this Au Playlist:                                              
1. If there's a new version of the theme that sounds better, that theme will be replaced with the new version.                                                                     
2. If a Au theme haves a motif that similar to that theme, it won't be added to this playlist.                   
3. If an Au theme sounds so bad that it should get a V2, it's added to the bottom Best to Worst themes

Update: I Updated picture because that other one was outdated.

An Once Upon A Time Undertale AU Compilation Mix 2025

UNDERTALE Soundtrack

Once Upon a Time

Not much to say for this one. It was fun experimenting with the composition.

001 - Once Upon A Time

ON THIS DAY, SO MANY DAYS AGO.
HUMANITY DECIDED THEIR CHOICE WAS SUPERIOR.
WITH SUCH HUBRIS.. MONSTER KIND LOST.
A SINGLE FLASH OF RED TO FILL OUR EYES AS WE WATCH, STONECOLD AND PARALYSED.
EVERYTHING IS IN RUINS
RUINS OF RUINS OF RUINS.
AND YET, A BACTERIA, A VIRUS SUCH AS YOURSELF PERSISTS.

@the_awful

1 - Point of no Return (Ramiyoru)

* Long ago, humans and monsters coexisted in harmony upon the surface of the Earth. 
* Their lives intertwined, they shared laughter, dreams, and the beauty of their world. 
* But peace is a fragile thing, easily shattered by fear and misunderstanding.

* It was an era of prosperity and unity, until the fateful day when tensions between the two races ignited into full-blown conflict. 
* The reasons for war have long been forgotten, buried beneath the weight of history. 
* In the chaos that ensued, the monsters, vastly outnumbered and outmatched, were driven to the brink of extinction.

* Forced to retreat, the monsters found themselves banished to a realm beneath the surface—an underground prison of eternal darkness. 
* Cut off from the sunlit world they once knew, they built a new civilization in the depths, clinging to hope of one day returning to the surface.

* Years turned into decades, decades into centuries, and the surface world forgot about the existence of their former neighbors. 
* Yet, the monsters endured, their spirit unbroken despite the harshness of their new reality.

* And so it was that many years later, fate would once again intertwine the destinies of humans and monsters. 
* On a quiet night, a child, the seventh of its kind, tumbled into the gaping maw that led to the monster's realm...
* A child whose arrival would set into motion events that would change the course of history.

* Little did anyone know that this child's journey into the depths would become a beacon of hope, a chance for reconciliation, and a test of courage and compassion. 
* For in the heart of darkness, where fear and despair lurk, a new story is about to unfold—a tale of friendship, adversity, and the quest for a peace long lost.

* This is the story of Undertale.

Echoes of Harmony

1) - One Fateful Day (jenfkejl)

CREDITS:
Full song by: @dashingtoadie-the-sequel
-----

[* this is the once upon a time replacement of my au.]

* long ago, two races ruled over earth: humans and monsters.
* one day, war broke out between the two races.
* after a long battle, the humans were victorious.
* they sealed the monsters underground with a magic spell.
* many years later...

mt. ebott
201x

* legends say that those who climb the mountain never return.

001 - once upon a time.

Check out the original Soundtrack:
https://tobyfox.bandcamp.com/album/undertale-soundtrack

001 | Beginning Anew

Song made by: https://soundcloud.com/siegfried-e-s-o

Join our Discord! - discord.gg/JyUy8tq

001 - Once Upon A Time (Siegfried)

Underfell take - Original by Vic/Underfella

Mimmky/Wiitorii
GenericAntagonist
Ramiyoru
Frappe

1 - Point of no Return (Ramiyoru)

Underfell Concept