As the GRINCH, it's your lifelong goal to steal Christmas. You must sneak through Whoville in 29 missions, destroying presents and collecting blueprints for an invention. Once you've found all the blueprints, you can build your invention and use it in later missions. When there are areas that you just can't seem to reach, you can send your dog Max to check things out. Will the Grinch be able to steal Christmas? That is entirely up to you.