For centuries the Avatar kept balance between the world. The fire nation was terrified of the avatar so they killed the last avatar. His name was Avatar Roku. But there was not only one avatar, there was thousands of avatars before him. They lived a normal lifetime. My grandfather, fit lord Sozin killed avatar Roku.
Elements
There were four elements people can control. Water,Earth,Fire, and Air. That is the avatar cycle. Each avatar would be born with a birth element. The Avatar is the only one In the world who can bend all four elements. But they have to master it in order to keep the cycle in place. For example, if you are born in the earth kingdom you have to master earth, than fire, air, and water. I am a fire bender.
The next generation
The next avatar was born an airbender. People bealeave he is dead because people have never seen an airbender in 100 years! Until now.
