Water, earth, fire, and air; those who can manipulate one of these elements are known as elemental benders, giving rise to the four nations of Water Tribe, Earth Kingdom, Fire Nation, and Air Nation. Only the Avatar can master all four elements, serving as a bridge between the nations and maintaining world balance. However, a hundred years ago, the Avatar mysteriously disappeared, leading to the Fire Nation's century-long war of conquest against the other three nations. Now, Kaen is transported into this world as a young firebender...