I’ve made a lot of tracks for Mecromage so far…more than for my Castlevania 3 tribute album in fact. We want to balance the music not just to the setting of a level, but the ‘role’ of a level as well.
For example, when playing a linear level (or a bidirectional level as popular in Castlevania 2), it’s ok to have uptempo, blasting metal as your main concern is getting from point a to point b.
On the other hand, exploration and non-linear sections are less likely to rock out, because the music starts to compete with the faculties needed by the player to enjoy the experience. Suspenseful and less “dense” music works better there.
Finally, within our levels, the pacing is apt to change whether due to a miniboss being encountered, a secret room, etc. The following song was meant for some action that takes place when the player stumbles into one such room, signaling an uptempo change of pace. It’s the music we used for the developement diary video: here’s the full version.