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Reason given: Add more unused tunes such as some from TCRF. Add unused music for Generations V and VI
|This article is a summary page for different variations of a glitches, etc. when talked about as a whole.|
Most music present within the Pokémon games have been applied to at least one map, or other in-game interfaces such as the title and the battling system. However, various tunes and sound effects exist in the Pokémon games which are never actually used without an external device.
Some music originates from older games. A remixed version of the title screen music from Pokémon Ruby and Sapphire exists in Pokémon Diamond and Pearl; however, it is never used in normal gameplay.
Other tracks serve a completely unknown purpose, such as an unused theme from Pokémon Battle Revolution.
Other tracks are altered versions of existing music, for example, an off-key version of the original music from Routes 206, 207, 208, and 211 accounts for several hundred inaccessible areas called Mystery Zone in Pokémon Diamond and Pearl.
Unused soundtracks in Generation I
In Pokémon Red/Blue/Yellow:
- There are three unused sound channels in Red/Blue/Yellow.
The following Game Genie codes will replace the Pallet Town music to use them:
In Pokémon Yellow: Only one unique unused track is currently known to exist within Pokémon Yellow.
- An unknown, unused tune exists within the coding of Pokémon Yellow. Interestingly, it does not exist within Pokémon Red and Blue, which may suggest itself as part of an additional planned feature. This can also be backed up by the fact that it belongs in the hex:20 soundbank (hex:28 soundbank in Japanese versions), used for things exclusive to Pokémon Yellow including the printer error theme, the Jessie & James encounter theme, and the Pikachu's Beach music. 
Japan exclusive tracks (Generation II)
As a method to obtain the GS ball to capture Celebi in Pokémon Gold, Silver and Crystal, the Poké-Communications Centre (PCC) was built into the final release of the Japanese versions of the games. A Mobile Adapter was sold separately which allowed the player to initialize the event by downloading it on their mobile and transferring it to their Pokémon game. However, since these features were never included in other versions of Pokémon Gold, Silver and Crystal, three unused tracks exist in non-Japanese games.
- Music which plays for a connection attempt with the Mobile Adapter.  (ID: 5E)
- The music played for accessing the Mobile menu. It also appears in Pokémon Stadium 2 as "sparse41.miniusf" where it is used for the menu for viewing videos of timed mobile battles transferred to Pokémon Stadium 2 via the Transfer Pak. (ID: 5F) 
- The music played in the Pokémon Communication Centre after the player successfully connects the Mobile Adapter for the first time. (ID: 66) 
Unused soundtracks in Generation III
Several unused tracks exist in Generation III which seem to be remixes of old songs from Generation II, such as Team Rocket's Theme. However, other tracks such as an unused track similar to Littleroot Town may have been used as test music. In Pokémon Mystery Dungeon: Red and Blue Rescue Team, two unique, unused tracks also exist within the game.
In Pokémon Ruby/Sapphire: The following unused tracks exist in Pokémon Ruby and Sapphire.
- An unused track which is a slightly different arrangement of Littleroot Town's theme exists in the game. 
- A remade version of the music played in the Poké-Communications Centre exists in the game but is never used. 
- A remade version of Team Rocket's Theme is another example of a track which exists in the game but is never used. 
- A remade version of the theme played when encountering Raikou, Entei or Suicune on Pokémon Crystal exists within the game, but is never used because Nintendo decided not to include the Legendary Beasts in Pokemon Ruby, Sapphire, and Emerald. However, Pokémon Colosseum and later Pokémon FireRed/LeafGreen decided to use the normal Cipher Admin music and the normal wild Pokémon music for the Legendary Beasts, respectively. 
- A remade version of the music from routes 38 and 39 exists within the game, but is never used. 
- A remade version of Pokémon Gold/Silver's original Pewter City/Saffron City remix exists within the game, but is also never used. 
An unused set of sound effects also exist within Pokémon Ruby/Sapphire, portraying a robotic female voice, similar to the The Bard (a male version) in Pokémon Emerald, who would also 'sing' a song to the player, based on the words they input. 
In Pokémon Mystery Dungeon: Red and Blue Rescue Team: Two unused tracks have been found within the coding of the original Pokémon Mystery Dungeon games.
Unused soundtracks in Generation IV
In Pokémon Diamond/Pearl:
- A remix of the title screen music from Pokémon Ruby, Sapphire and Emerald exists in the game entitled "SEQ_TEST_TITLE". As its name suggests it is most likely a placeholder to test that music on the title screen will play correctly before the actual title screen music was composed. 
- A slightly off-key version of routes 206, 207, 208 and 221 is played in most of the several placeholder areas entitled Mystery Zone within the game which exist in between real locations. It is named "SEQ_DUMMY", which suggests that it is to compensate for music in these locations which would otherwise be undefined. 
- Exclusive music for a battle against the Tower Tycoon in the Battle Tower exists within the game, but is never used for unknown reasons. Nintendo decided to use the Champion Battle Theme instead. This music is a slightly different version of both the music played against a Gym Leader and a member of the Elite Four. 
- An alternative arrangement for the music in Jubilife City exists and can sometimes replace the music of areas named "Jubilife City" while in the tweaking void.
In Pokémon Mystery Dungeon: Explorers of Time and Darkness:
-  - A remixed version of the Makuhita Dungeon from Pokémon Mystery Dungeon: Red and Blue Rescue Team exists within Pokémon Mystery Dungeon: Explorers of Time and Explorers of Darkness but remains unused, likely because of the fact that the Makuhita Dungeon was not included in these games. This may imply that a similar dungeon was originally intended, or that the sequels were based off of the original games.
In Pokémon Battle Revolution:
- Unused music exists for possibly an extra colosseum or waiting screen. It is a rather smooth and steady theme which could have once been planned for Neon Colosseum 
- Many files denoting the narrator's speeches in Pokémon Battle Revolution exist but are completely blank and are never used in the final game, which may suggest that these are deleted versions of speeches from an earlier version of the game.
- A file denoting one of the narrator's speeches exists as "ba120_0". In this speech, the narrator says "Lagoon Colosseum, Tournament Battle, first match." This may suggest that at least at one point in the game's development Lagoon Colosseum was intended to be featured in one of the main Tournament challenges. This track is never used in the final game because Lagoon Colosseum is only accessible via a Random Wi-Fi Match, a Friend Battle or the DS Multiplayer Mode. 
- In the file "la030_0", the narrator speaks the words "Surrounded by cascading water, the battle is about to begin." This file is never used in the final game and may have once been associated with Lagoon Colosseum as backed up by the narrator's description of the area and the final name "la030_0" where "la" may be an abbreviation of Lagoon.