In the world of Avatar, hundreds of years before Aang and his friends, there were two avatars. The tale of Yin and Yang has been lost in history, only found deep within Wan Shi Tong's library. Their story takes place after the previous water tribe avatar died. The earth kingdom citizens awaited the arrival of the new avatar. Little did they know the avatar's egg in the womb would split into two, thus creating two avatars. This is the tale of Yin and Yang, two avatars in one chaotic world.