kinda spoiler-y so dont look if u havent played the latest chapters of deltarune but ive been listening to the sountrack now that ive finished ch3/4 and...
i really like how the battle theme's been evolving throughout the chapters and how its reflecting the story!!
in chapters 1 and 2, rude buster starts off as adventurous and playful. its groovy and lighthearted, which makes sense considering there isnt a particular real danger except for the king and jevil, and many of the foes you meet very easily become your allies. hell, lancer and susie's hijinks throughout chapter 1 arent really evil plots. its more like a bunch of teenagers playing pretend, which is essentially what the dark world is at its core. queen in chapter 2 isnt even a particularly evil force, just someone trying to do good through uninformed means. its emblematic of a couple of kids just hanging out and having adventures and making friends
ruder buster in chapter 3 leans even more heavily in the light hearted theme. with most of the adventure taking place on a tv show, has a more showboat-y nature to it, which makes sense since the gang is trying to show off.
then comes the shift that happens between chapter 3/4, when the heroes come face to face with the overwhelming power of the knight and the dangers of what the knight stands for. the battle theme changes to from now on post the knight encounter, as if signifying that the heroes are now aware of the stakes at hand. of course its still pretty light hearted, but the theme takes itself a bit more seriously now. while there's still an adventure to be had and friends to make, the fate of the world hangs in the balance (signified by the melody shift to the dont forget leitmotif), and while we're still having fun we also have to take this seriously and protect the people that we meet from danger. the tl;dr of this is that holy shit i love musical story telling and i hope that the battle theme keeps changing over the next few chapters lmao