I vaguely remember this musician that did Silent Ponyville music and can't seem to find their channel anymore. Aaron (Percipientfish) confirmed that this belonged to them (https://www.youtube.com/watch?v=RFOc6qMwtLQ).

Here's the score for it for anyone interested - http://www.mediafire.com/file/6ezvk787yldhpkh/A_shade_of_regret.pdf/file

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