Castle of Illusion is often seen as the absolute must-have Mickey Mouse game released for the Sega Genesis, but World of Illusion is a game on-par with its predecessor and probably out does it in some senses. While it's a shorter game and an easier one at that, World of Illusion never fails to charm based on its fantastic graphical capabilities, its amazing soundtrack and its world. The game plays a little differently than Castle of Illusion, your main attack is actually a cape-swipe… it's weird but it totally works and I couldn't imagine it any other way. Playing this game solo is always a fantastic affair, but playing it with two players is where it really shines and is the prime way to play it.
World of Illusion is exactly what you want from a Disney game starring Mickey Mouse. The world is fantastically intricate and colorful, Mickey and Donald are very personable and most importantly, the game is just hella fun to play.