There are two requirements for creating believable characters in today’s games: the first is that characters need to make the correct decisions (artificial intelligence [AI]), and the second is that they need to look good when acting on those decisions (animation). With the heavy visual focus in today’s games, it is fair to say that an AI system will live or die based on the quality of its animation system. Smart decisions won’t matter much if the animation system can’t execute them in a visually pleasing manner.