It's the first piece of music that I geniunely liked a lot that's discovered by myself, and it's safe to say that it shaped most of my music taste in the future.
It's a midi, with 3 main parts that I can listen to (the main melody, the supporting melody, and the kicks). It's very short (1:49) as a video game soundtrack, but it has all the things needed for becoming a geniunely simple yet complex yet emotionally impacting music.
Personally I like listening to the supporting melody for the most part, because in my opinion it's what made Heartache so interesting to listen to despite all these years.
Also I do know about the UNDERTALE lore, but I'd prefer keeping that for random instead of music. The same goes to music videos and illutrations of the music in the future, I want these to be about the music only.
Also pardon me that I don't know much about music, it's just a hobby of mine to listen to them, but I'm always eager to learn about it.