Each level exists within the large titular castle and the player must defeat enemies and bosses by jumping on them, or collecting apples and marbles to use as projectiles. The player can also collect icons to increase health, collect extra lives, or gain bonus points. After defeating a boss, the player is given a gem. When all seven gems are collected, the player can build a rainbow bridge that allows him/her to walk into the castle's tower for a final battle against the witch (who in her youthful form resembles the Queen Grimhilde).
Castle of Illusion Starring Mickey Mouse (NA)
20th November 1990
Castle of Illusion Starring Mickey Mouse (JPN)
21st November 1990