Puzzle games have always existed within a predefined set of rules. Scribblenauts kicks those rules in the face, instead defining its own path towards the future of gaming. Despite being the first game that I got to try at E3 2009, it was the one that I thought about the most throughout the rest of the expo. A 2D puzzle game by design, Scribblenauts is only limited by what your imagination can come up with, offering thousands of unique possibilities which guarantees that no two people's experiences will be remotely similar. So what exactly is it?