Castle Master is the fourth and final individual game to use the Freescape first-person solid 3D game system (after Driller, Dark Side and Total Eclipse). As a Prince or Princess armed with a slingshot, you have to explore a medieval castle to free your beloved from the evil Magister.
Gameplay combines action and puzzle-solving, across four primary towers with three levels each. Doors must be opened using one of the ten included keys. These are unmarked, as are the various potions - making it a challenge to know which keys open which doors, and which potions are beneficial.
Contact with ghouls drains your energy, as does falling too far (there are narrow pathways to negotiate), while eating cheese can replenish this. Movement and aiming are controlled separately.