Water. Earth. Fire. Air.Long ago, the four nations lived together in harmony. Then everything changed when the Fire Nation attacked. Only the Avatar, master of all four elements , could stop them. But when the world needed him most, he vanished. A hundred years passed and my brother and I discovered the new Avatar, an airbender named Aang, and although his airbending skills are great, he still has a lot to learn before he's ready to save anyone.But I believe Aang can save the world.