Fellswap is by Blackggggum and adopted by the community.

https://www.youtube.com/playlist?list=PLkWML0ek1Zxidh-ST7vA5Tc_wHKwP3YTH

Remember these are not all unofficial, these are just my opinions of what the themes can be.

Fellswap/Swapfell RED (description for others themes)

Fellswap Gloomy

UNDERTALE XI multiverses of other multiverses

underfell

Fellswap

Toby Fox - UNDERTALE Soundtrack - 68 Death By Glamour

Underfell Megalovania

Underfell Bonetrousle

I heard Underfell was a thing so I did a thing.

Undertale - Sans & Papyrus Vs. Sans & Papyrus (Underfell AU)(Mashup)

inb4 megalochara comments

cover art by me

BPM: 115
Key: G# minor

[Undertale AU - Underfell] M.E.G.A.L.O.V.A.N.I.A

[DO NOT REUPLOAD THIS OR ANY OF MY SONGS TO YOUTUBE WITHOUT MY EXPLICIT PERMISSION.]

Swapfell is a dumb AU. I'm working with a team of cool dudes to make it not as dumb. The first step to being not dumb is cool music. Ask Altertale.

Art by Ilikepony on dA -> http://ilikepony.deviantart.com/art/Swapfell-Asgore-632708685

Swapfell - A Watchful Eye (Fallen Down)

Dynami FlP by https://soundcloud.com/decimate-doom
MEGALOGLAMOUR MIDI by https://soundcloud.com/keno9988ii

Glamouynami (Updated Again)

A track made for the Swapfell official fan-game. music by Mr. stardust. enjoy!here is a link to the gamejolt page show them the love and suppourt they deserve! gamejolt.com/games/undertale-au-swapfell/165436

[Swapfell AU] I Don't Know How to Love You, Darling

Requested by Mason Mosher
MOKEYLOKRIMA FLP belongs to @falexinyt
Vroom (Sonic in Sr Pelo Style): http://tocinin.deviantart.com/art/Vroom-Sonic-in-Sr-Pelo-style-673814197

SONICLOKAOS (CHAOSLOMANIAC V2 in the style of MOKEYLOKRIMA)

This track apparently was not deleted after I got the account, so I'm leaving it up.

Vampire Room (Misha's Theme) (Old)

The Fallen Down replacement for Gloomy!FellSwap.

Gloomy!FellSwap - Intoxicated Kindness

Here's the update to Jack Frost's IRSE (Name by Violet >w<)
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AU is owned by me and Violet ^w^
Rise of the Guardians is owned by Dreamworks

Hope you guys like it! ^w^

ANIMATION: A Glitched Plot - Distant Memories... Of Fun Times In The Snow

custom Gaster theme for a friend by the name of Mikele_11
https://soundcloud.com/mikele-11-631548532 heres his account.

GT!Sinsy's Theme

*Let me tell you a story,
*a story of old.
*Long ago, there were two races:
*Humans and Monsters.

Composer: Ectoplasmiic

Gloomy Studio Fellswap - A Story of Old

Gloomy Studio FellSwap - Time to Start

*Hoi!
*i'M tem, tEmmie tHe TeM!

Composers: MaximusGames and Purrsum

Gloomy Studio FellSwap - Your Onoi Tem!

*HEYA, HUMAN!
*MY NAME'S PAPYRUS, AND I'M PRETTY MUCH...
*THE COOLEST PERSON AROUND.

Another "I'm not dead" track.
Being used in Gloomy Studio: Fellswap

Swapfell - Terrifyingly Cool Dude

(Lot's of fixes have been made.)

*Let me tell you a story,
*a story of old.
*Long ago, there were two races:
*Humans and Monsters.

Composer: Ectoplasmiic

Gloomy Studio FellSwap - A Story of Old (V2)

(Completely changed.)

Start
Reset

Composer: Ectoplasmiic

Gloomy Studio FellSwap - Time to Start (V2)

(Unused V1 by Ectoplasmiic.)
*Oh, hello human...
*I am Asgore, guardian of the RUINS.

Composers: DavidJacomeTCP and Ectoplasmiic

Gloomy Studio FellSwap - Intoxicated Kindness

Hope u like it
discordapp.com/invite/skPabQ8

[Underfell] Ruined Fortress (UPDATED!)

This is a remix of Freaktale Megalo Strike Back called as "Rouge Strike Back" and Freakfell is a Freaktale and Underfell AU combination, the fell-ified version of Freaktale. Freaktale AU designed by Le Fun Shark, but Freakfell AU designed by me.

Artwork by Fezak: https://aminoapps.com/c/undertale-aus/page/blog/freaktale-rouge-ftdacc-entry/BVdm_RJiwuzXxxNznoJWlYQNaVKz2130ok
Music and Freakfell AU by Me
Credit if you use!

Freakfell - Rouge Strike Back (Megalo Strike Back Underfell Remix)

"I have NEVER been insulted like this in ALL MY LIFE!!"
"Your mere presence has just… made me SO…"
"Mad. Livid. ABSOLUTELY ENRAGED!!!"

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Make sure to support the composer of this track! @trezzyisstillhere969

TS!UNDERSWAP Soundtrack

TS!UNDERSWAP Soundtrack - 008 - Enter! A Furious Foe!

Credits:
Art and AU by @they-called-us-momo

Links:
FH OST playlist: https://soundcloud.com/arku-razumi/sets/fallen-history-ost/

-------------------
Welcome to ArkuArk1ve.
This account is an archive account of the musician Arku Razumi(@they-called-us-momo)
The purpose of this account is to preserve Arku's content in an accessible, safe place, similar to xReamed and other archive accounts.

Read the account's description for more info.

[Fallen History] ''too fabulous to fight..''

The official soundtrack of GS!FellSwap, created by Gloomy Studio.

Discord Server: 
https://discord.gg/WKcYHeJ

Gloomy Studio FellSwap - Your Onoi Tem!

Gloomy Studio - FellSwap OST