From the back of the book:
Pack your pencils and prepare for a journey to the heart of the universe: the planet Sketch, where good and evil are locked in constant struggle, with fame and fortune hanging in the balance!
Play anything you can draw, from stick figures to the Mona Lisa. Create heroes who want to save the city, or villains who want to destroy it. Charge into battle, or gather a group of friends and explore the strange and wonderful world of Sketch. Anything is possible!
Besides, how many games encourage you to play with your crayons again?