Book excerpt: Game Design Foundations, Second Edition covers how to design the game from the important opening sentence, the "One Pager" document, the Executive Summary and Game Proposal, the Character Document to the Game Design Document. The book describes game genres, where game ideas come from, game research, innovation in gaming, important gaming principles such as game mechanics, game balancing, AI, path finding and game tiers. The basics of programming, level designing, and film scriptwriting are explained by example. Each chapter has exercises to hone in on the newly learned designer skills that will display your work as a game designer and your knowledge in the game industry.