A mostly linear exploration of the castle is broken up with boss fights, many of which are characters from the original arcade game, but not all. Many of the rooms seen in the original are seen again, though some are modified. New mechanics are introduced by the Dragon Essences that grant new powers.
The castle's exploration is a linear journey punctuated by boss battles, with some bosses being characters from the original arcade game and others not.  Many of the rooms seen in the original version reappear, though some have been altered. New abilities are introduced through Dragon Essences, which grant new powers.