In the Dungeons & Dragons fantasy role-playing game, creature types are rough categories of creatures which determine the way game mechanics affect the creature. In the 3rd edition and related games, there are between thirteen and seventeen creature types. Creature type is determined by the designer of a monster, based upon its nature or physical attributes. The choice of type is important, as all creatures which have a given type will share certain characteristics (with some exceptions). In 3rd and 3.5 editions, type determines features such as hit dice, base attack bonus, saving throws, and skill points.