Milon, a child of the Kingdom of Hudson, must go on a quest to rescue Queen Eliza from an evil wizard who has taken over her castle as well as the musical instruments that the queen's subjects use to communicate with each other. Milon must recover the stolen instruments and rescue the queen from the wizard. Armed only with a magical bubble-shooting ability, Milon makes his way through the rooms of the castle finding items and money that can help him progress.
Gameplay involves navigating Milon through various rooms in the castle, fighting enemies and solving puzzles along the way. The game requires strategy and quick thinking as Milon uses his magical bubble-shooting ability to overcome obstacles and defeat foes. With its blend of action, exploration, and puzzle-solving, Milon's Secret Castle is a challenging and exciting platformer that will keep players on their toes.