Hands down, this is my favourite SNES game, beating out even A Link to the Past.  There are over 60 levels, all of which are massive and full of challenges and items to collect.  The real fun thing is learning to manipulate the egg toss, and defeating enemies in seemingly inaccessable places.  The graphics are colourful and unique.  This is the pinacle of platform gaming, and it has never been surpassed and perhaps only matched by Super Mario Bros. 3.