Avatar Zuko: Book 1 - Fire

The Fire Nation has become invincible.

During the reigns of Fire Lords Sozin and Azulon, the airbending, waterbending, and earthbending Avatars of the Avatar Cycle have been killed. With a Fire Nation Avatar on the way, Prince Ozai has plans of overthrowing his brother and father to become the next Fire Lord and use the firebending Avatar to conquer the entire world. Everything changes when the new Avatar turns out to be Ozai's biggest disappointment: his own son.

DISCLAIMER: I am not the first person to write an "Avatar Zuko" type of fanfic, but the story, plot, original characters, and "new" world are created by me and are entirely my own creations (other than the pre-existing Avatar concepts, of course.)

Water
Earth
Fire
Air
Long ago, the four nations lived in a state of separation. Then, everything changed when the Fire Nation began their quest of uniting the world.
Only the Avatar, master of all four elements, stood in the way of the Fire Nation's goals. But when the Fire Lord feared him most, he was killed.
A hundred years have passed and now the airbending, waterbending, and earthbending Avatar's have been killed. Now, a firebending Avatar has been born into the cycle.
With the help of the new Avatar, the Fire Nation will achieve victory and rid the world of the four nations and unite the world in flames.