19. Cave Story 3D OST: Gravity (Boss theme 1)
This is a generic boss theme, which I remember from a number of Balrog battles. This is the 3D remix version; the original will be up shortly.
20. Cave Story OST: Eyes of Flame (Boss theme 2)
This is the second generic boss theme, which I remember from the battle against Balfrog. Geez, that guy was annoying.