Avatar (2009 film) themselves to change into a Na'vi. "Avatar: A Confidential Report on the Biological and Social History of Pandora", a 224-page book in the form of a field guide to the film's fictional setting of the planet of Pandora, was released by Harper Entertainment on , 2009. It is presented as a compilation of data collected by the humans about Pandora and the life on it, written by Maria Wilhelm and Dirk Mathison. HarperFestival also released Wilhelm's 48-page "James Cameron's Avatar: The Reusable Scrapbook" for children. "The Art of Avatar" was released on , 2009, by Abrams Books. The book features
Avatar: The Last Airbender among the four nations, and act as a mediator between humans and spirits. When the Avatar dies, their spirit is reincarnated into the next of the four nations in what is known as the Avatar cycle: the Fire Nation, Air Nomads, Water Tribe and Earth Kingdom. An Avatar is required to master each bending art, beginning with the element of their home nation, and proceeding to learn the others in the order of the Avatar cycle, starting at the age of sixteen. Avatars also possess the ability to enter a condition known as the Avatar State, in which they gain