From the back of the box:
"Now you're really in trouble" said the Evil Wizard. "I'm turning you into a ball of air and sending you into my mansion, with over 250 rooms, to search for the Spellbook that may give you the clues on how to transform yourself into a human again. It's not as easy as it sounds, for you, as the ball of air, have a slow leak, and you'll need to jump on an air pump in some rooms to remain inflated. Take heed, for if you pump up too much you will burst! If you are lucky enough to find the book in these rooms, you'll next have to pick up the objects I've left, such as: crosses, tins of beans, a Buddha, a dragon statue, a pumpkin, a flask, and even crates that you'll need to get over treacherous obstacles! This is your one chance for survival", he cackles.
"Sounds easy" you laughingly boast to the Evil Wizard.
"Oh! Does it now?" He sneers, "Well, I'm also putting spikes in these rooms that will take your breath away, as well as killer pads on the floor. Your have no chance for success...Hee! Hee! Hee!"