Move Mario through the castle and its many secret worlds to uncover and accomplish the various goals for each course. If you touch an enemy you will lose some of your power. If your Power meter is empty or you fall through a bottomless hole you will lose one life. If you lose all your lives, your game will end.
If you want to leave the course you are currently in, let Mario come to a stop and press . At the Pause Menu that appears, select EXIT COURSE to return to the main hall of the castle.