Unlisted music tracks

Undertale features several unlisted music tracks that are not part of its official soundtrack. These range from full-length tracks to short jingles, and occasional sound effects. Most of these music tracks play in various areas throughout the game, or are Genocide Route-exclusive tracks. Non-typical gameplay music is also documented, such as Dogcheck tracks.

General in-game tracks

Tracks that play in various areas throughout Undertale. The list is sorted in alphabetical order.

Cool Beat (mus_coolbeat)

Cool Beat (JP: クールなビート) plays when sleeping at the MTT Resort in Hotland. This track is also featured in Chapter 2 of Deltarune as coolbeat, where it plays in the Sweet Cap'n Cakes shop at the Cyber Field when selecting "Talk" and choosing the topic "Performance". It also plays in their shop in Castle Town when selecting "Play Music", where it is called "Cool Beat".

mus_dogroom

This track plays in Annoying Dog's room in the mysterious door area of Snowdin.

Dog Casino (XBOX) (mus_dogshrine_xbox)

This track only plays on the Xbox One and Xbox Series X|S versions of Undertale in the Dog Casino. It was officially titled in the UNDERTALE 6th Anniversary Stream as a "RARE" track, along with an explanation of where it came from and the 1000-particle dialogue. In the stream, it is pitched up by 2 semitones compared to the in-game file and briefly fades out to let Mew Mew's Super Secret Song play.

mus_f_saved

This track plays when ACTing during the various SOUL phases in the battle against Omega Flowey.

mus_sfx_dogseal

This track only plays on the Nintendo Switch versions of Undertale, at the Dog Shrine, when interacting with the mysterious seal that resembles a dog.

mus_snoresymphony

This track plays when sleeping at the Snowed Inn, it features a rendition of Determination performed by the snoring guests.

mus_woofenstein_loop

This track plays during Endogeny's battle before meeting the spare conditions. It was made using the Experimental-Woofenstein preset from the Ultimate Sytrus Pack for FL Studio. The name Woofenstein is presumably a dog-related pun on Wolfenstein.

snd_grandpatemi

This track plays when refusing to give Temmie the Temmie Flakes in an encounter, as the quote "can't blame a BARK for tryin'..." appears. It is reminiscent of the intro to Metal Crusher.

In the Undertale Demo, the same file appears as grandpasemi. Grandpa Semi was a cut character who may have been planned to be connected to Papyrus and Sans, with "Semi" possibly referencing semi-serif fonts or the SEMI OCR font. An unused Cell Phone call asking for a pizza, similar to the one that the protagonist can randomly receive in Snowdin from Alphys in the final game, is referenced in the demo's code as Grandpa Semi's line.

This sound is also featured in Chapter 4 of Deltarune, when resetting Mike's minigame scores with the MichaelBomb, where it is internally referred to as snd_mike_reset.

Genocide Route tracks

While Deltarune's Weird Route uses alternate tracks encoded as their own files, the Genocide Route simply alters the volume and pitch of most background music tracks to provide an unsettling atmosphere. Some of the tracks that are encoded as their own files include:

mus_toomuch

This track plays after the message "But nobody came." appears during an encounter once an area's kill counter has been fulfilled, replacing that location's regular background music. This track is a part of Your Best Friend playing at 1/13th speed (~0.077x or ~92% slower) with added reverb.

mus_zzz_c

This track is a short ambience that plays during the fallen human's introduction at the end of the Genocide Route.

mus_zzz_c2

This track plays immediately after the end of the fallen human's dialogue if the player chooses "DO NOT" when they offer to destroy the world. It accompanies the scene where they approach the screen while laughing.

Sound Test tracks

Main article: Fun value#Sound Test room

By traveling upward from the "Box Road" SAVE Point intersection in Snowdin, if the fun value is set to 65 and Papyrus has been defeated, there is a 50% chance for a hidden "Sound Test" room to appear. The menu contains three very short looping tracks and one longer track, which, once selected, cannot be deselected. None of these tracks are used elsewhere in the game.

Dogcheck tracks

These tracks play when triggering a Dogcheck, a fail-safe that is activated when attempting to access inaccessible or nonexistent rooms.

Dance of Dog (mus_dance_of_dog)

Dance of Dog (JP: イヌダンス) plays in an error room containing a dancing Annoying Dog. This error room can be accessed by modifying the SAVE file to load a Dogchecked room. The track's speed is randomly chosen between 95% and 105% of its base speed.

It played during the UNDERTALE 6th Anniversary Stream after the rest of the pre-show tracks, as the Annoying Dog had been woken up. It is also present on Side D of the Fangamer vinyl for DELTARUNE Chapter 2's OST, where it is extended to 2:03 and plays at 100% speed.

mus_sigh_of_dog

This track plays in an error room containing a sleeping Annoying Dog. The track's speed is randomly chosen between 80% and 100% of its base speed.

Outside the game files

Other tracks publicly released around Undertale that are not directly part of the soundtracks.

Annoying Dog PS4 Theme

Used for a 2017 Famitsu Exclusive PS4 theme featuring the Annoying Dog. It was officially titled in the UNDERTALE 6th Anniversary Stream as a "RARE" track, along with an explanation of where it came from. It also played in the INDIE Live Expo 2020 stream, during Toby Fox's message.

Mew Mew Intro (Trailer)

Mew Mew Intro (Trailer) (JP: みゅうみゅう イントロ (トレーラー)) was used in the 2018 Nintendo Switch Release Trailer, for the intro animation featuring Mew Mew. It is included on the UNDERTALE FAN SELECTION CD.

See also

• Unused music tracks
• Hidden music tracks article on the Deltarune Wiki