Unused Game Soundtracks?

[Random Talking Bush]

For unused tracks, there's a few of them that I know of. There's probably the most well-known, simply named "Advent" from Banjo-Kazooie...
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The other most well-known one being Hidden Palace Zone this song from Sonic the Hedgehog 2.
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Then there's also this tune that is hidden in the PC version of Sonic & Knuckles.
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3D Dot Game Heroes had a second boss theme they never ended up using.
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Mega Man V for the Game Boy had a handful of unused or alternate songs, this one is an example.
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And technically I'm counting this as unused since DuckTales Remastered snuck it into its files but never used it, but Transylvania had a completely different song in the prototype versions of the game.
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And Jazz Jackrabbit 2 had not one, but two remixes of the original's bonus stage that never ended up being used.
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