So.... Undertale is kind of a masterpiece, and needless to say, I was blown away by the complexity of the soundtrack.
In addition to a ton of memorable and unique character themes, the Undertale soundtrack makes admirable use of leitmotivic development and foreshadowing and even some musical misdirection. It also features some very subtle and clever allusions to to other soundtracks. I thought perhaps we could take a crack at unpacking some of the themes, how they're constructed, what they're trying to say, how they change as the plot progresses, etc.
This is impossible to do without massive spoilers, so probably nobody who hasn't finished the game should be reading any of this.
To kick it off, I'll start with ONE small thing I thought was wonderful: The song you hear at the Game Over screen is a statement of Asgore's theme (I'm pretty sure it's Asgore's theme anyway, though there are probably many many ways to interpret it), and it's also Asgore's voice urging you to stay determined and try again. This would hint at the tragedy of his story, the ambivalence of his role as both "end boss" and "needs your help desperately" IF you knew from the beginning what the theme meant. But the it doesn't get formally introduced until the final battle with him and this creates tremendous build-up and anticipation. It also gives you a lot to pay attention to and ponder during the second playthrough. The theme itself is in dorian mode which makes it sound simultaneously mysterious, heart-breaking, and uplifting.
What are some things that struck you about this game's music? What important themes can you identify and how are they used?