My take on the Underswap soundtrack, using the "official" swaps. Expect to see lots of Moonswap and Tonyswap tracks, but definitely go check out TS!Underswap and BelowExchange (and all the others) as well (if you haven't already).

underswap by ur mom lol!!!!!

Full List of Swap AUs Used (in order of appearance):
BelowExchange
MIRRORSWAP
Moonstriker the Musical: underswap
Undertale: SWAPPED
Junnboi!Underswap (Take II)
Tony Wolf - UNDERSWAP Soundtrack
TS!Underswap
Inverted Fate (don't kill me please)
skyswap
UNDERSWAPERD
Euniswap
Our UNDERSWAP Dumpster
POLTERSWAP
Snolid Ice's Ironic Underswap
UNDERSWAP*
Underswap by Temmie Chang
Underswap: Distrust
Underswap: Apposite Day
Underswap: Distrust (Expert Mode)
Underswap: Unreasonable Hatred
Underswap: Revenge

Underswap Soundtrack

If you press "U", this leitmotif will play.
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Undertale was created by Toby Fox
In an alternate universe, 'Underswap' was created by Temmie Chang
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Leitmotif:
- Uwa!

☂ Ting-a-ling ☂

Art by @the_freaking_weirdo

*Welcome to the SANCTUARY, young one.
*The archeological remains of the subterranean.
*Prior to being flooded, many used to dwell in these ancient relics. 
*However, today I am going to welcome you...
*...to your "New Home".
*Err... you may wallow in its unusual atmosphere.
*Though I hope it will not get you... soaked to the skin, hohoho.

*The water rushing down from the unknown fills you with HOPE.
*Go ring your first bell!
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Undertale was created by Toby Fox
In an alternate universe, 'Underswap' was created by Temmie Chang
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Leitmotif:
- Once Upon a Time
- Start Menu
- Undertale
- Memory/His Theme
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As stated in the previous track, the reset bell from waterfall swaps with the save point. If you somehow die, you'll be brought back into where you ring your last bell! Related to the sanctuary, the little mouse from everywhere swaps with the spiders from the bake sale location. If you like cheese, consider buying them for only 7S! And just as importantly, have "faith" in yourself to the end!

☂ Bad Weather for a Stroll ☂

*I must say...
*The way you tackled those puzzles was impressive!
*Even though they were solely for beginners.
*Now, now, I have something quite requisite to request from you.
*I want you to walk to end of the room.
*All by yourself...
*It is to demonstrate your courage.
*...and to keep your body and soul from the opponents in the wind.
*Please forgive me for this, young one...
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Undertale was created by Toby Fox
In an alternate universe, 'Underswap' was created by Temmie Chang
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Leitmotif:
- Bereavement
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This takes place in a long bridge, which is an equivalent to the long hall.

underswap - Test of Courage (OUTDATED)

BELOWEXCHANGE
The RPG that can have a true happily ever after.
If you want it to.
--

This is celebratory thing 2/3 for BE's one year anniversary! I wanted to have some rendition of that UT promo art done for this, but not all of the character designs are finalized yet rip
Thank you again for your support everyone, it's been a great year! Plenty more stuff on the way!

Bonedoggle (trailer ver.)

Original arrangement "Flowey Village" by Grassinio: https://soundcloud.com/grassinio/underswap-flowey-village
Arrangement made by @dashingtoadie-the-sequel

Unfriendliness Pellets

* Dummy looks like it's going to fall over.

Original arrangement "Flowey Village" by Grassinio: https://soundcloud.com/grassinio/underswap-flowey-village

How To Talk To Dummies

UNDERTALE By Toby Fox
DELTARUNE By Toby Fox
UNDERSWAP By Hatsune Miku/Tony Wolf
MIRRORSWAP By @frisk-reborn-again
This account is run by @frisk-reborn-again
Song By @frisk-reborn-again 
Sprite By @takextracrumbs

PS5 Trailer Theme

*Ah... that troublemaker is always so persistent.
*My deepest apology for not arriving sooner...
*Nonetheless, perhaps an introduction is a must.
*Howdy, my name is ASGORE DREEMURR.
*The honorable baron of the waterlogged SANCTUARY.
*Do not worry, young one.
*I am not going hurt you.
*But instead, I am going to protect you from any imminent danger.
*Please, enter through this water barrier.
*For we must gather way forthwith.
*There is so much for you to familiarize yourself with.

*It has been quite a long time since a human has fallen down into the subterranean.
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Undertale was created by Toby Fox
In an alternate universe, 'Underswap' was created by Temmie Chang
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Leitmotif:
- Small Shock
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Asgore swaps with Toriel, definitively. Instead of wielding 'fire magic', he and Toriel wield water crystal magic! Asgore is an old farmer living in a flowering ranch with a hobby for playing guitar. The reset bell from waterfall swaps with the save point, and is now white/silver-colored. And just as importantly, have "faith" in yourself to the end!
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Wow, an update! (I've been waiting for this to be uploaded lol) But anyway, I decided to use genesis instrumentation since SEGA and Nintendo swap in this one. Don't worry, if you like the old one better. I still have it uploaded, just not marked as official anymore.

☂ Old but Gold ☂

* Young one...
* Please forgive me for delaying the inevitable...
* But you must prove your strength.
* Then, you can leave these deadend woods...

Arranged by @dashingtoadie-the-sequel and @junnboi-the-fourth
Name idea by @onehundredandtwentyeight

Heartburn (NEW)

*From here and only here, you can reach the rest of the Underground.
*I will be the bigger person here, and give you a chance to return upstairs without repercussion.
*I suggest you weigh your options.
--

This track has no official name in Undertale, but it's this one https://www.youtube.com/watch?v=XuyiC_L9EiU
--

Plays during Part 6 of the BelowExchange writeup, which you can find here:
https://docs.google.com/document/d/1AEN3DP9GFcphFSIIxg5XPb5KhZ39-TchQxPoiK13WqM/edit?usp=sharing

Below Asgore's Home

Leitmotifs:
Reuinited
Stronger Monsters
Respite

The Tale [A Frisk Once Upon A Time]

Let's Start [A Frisk Start Menu]

Music for the Underswap game 8y Team Switched. you can follow the project here:
http://gamejolt.com/games/undertale-underswap/160094

UNDERSWAP - Resolution

I wanted to do another IF track that wasnt interchangeable with Underswap but bones, heya, heh, and sup were already taken.

IF has a lot of Sans tracks.

Creds to Keno for the thumbnail. Also, for the remainder of September, I'm gonna do only Sans-themed songs.

Inverted Fate - skeletwo.

[Underswap] Ghost Fight [final update]

[UnderSwap] Uwa! Swapped Worlds!

003 - Talking Cat

"WHEN EVERYTHING IS FINALLY READY,"
"HOWEVER LONG THAT MIGHT TAKE..."
"IN THE END, IT'LL HAVE BEEN WORTH THE WAIT!!!"
"BECAUSE I, THE GREAT PAPYRUS,"
"WILL FINALLY HAVE MY TIME TO SHINE!!!"

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Make sure to support the composers of this track! @jacksqrd @r3zzo

TS!UNDERSWAP Soundtrack

TS!UNDERSWAP Soundtrack - 028 - PAPYRUS!!!

"It's such a pleasure to have you here, young one."
"I know that your journey thus far has been difficult..."
"But now, you have nothing to worry about."
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Make sure to support the composer of this track! @robinblend

TS!UNDERSWAP Soundtrack - 022 - A Place To Call Home

"Wow, so many cool toys...!"
"I hope someone enjoys them."
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Make sure to support the composer of this track! @robinblend

TS!UNDERSWAP Soundtrack - 023 - A Place To Call Home (Music Box)

planning to start making music sometime in the future... maybe.

but for now i'm just a playlist maker and general commenter.

have this while you wait: https://youtube.com/channel/UCcRPbT2BQyDXm8rQncqwz5A
working on too many projects, if you're curious about which ones exactly i work on check my writing playlist

discord: bowserman9

Underswap Soundtrack

Bowser Man