He is an incarnation of the "Avatar", the spirit of light and peace manifested in human form. As the Avatar, Aang controls all four elements (water, earth, fire, and air) and is tasked with bringing balance and keeping the at peace. At 112 years old (physically 12), Aang is the series' reluctant hero, spending a century in suspended animation in an iceberg before being discovered and joining new friends and Sokka on a quest to master the elements and save their world from the imperialist Fire Nation.