Green ninja in a world of bending

Our hero finds himself in a different world similar to his but also different, a place where 4 nations used to live in harmony but that all changed when the fi-"Oh my gosh shut up already dude, and who even are you"

Will our hero be able to bring peace back with his new allies and his new elemental master?

"What are you yappin about"

Listen here you little sh-

Green ninja in a world of bending