Avatar: The Untold Legend
Lian was raised in Northern Air Temple, by monks. He was a quick learner and was expected to be a Master Airbender in such young age, but… As he grew up, he started to wonder the places outside the temple. When he became 18, he left the temple without becoming a Master.
It can’t be said that he’s aggressive. He’s a logical and peaceful airbender, and wants to stay that way. All he wants is seeing new places, meeting new people and living new adventures.