Chey

History
Chey is a former Fire Nation army soldier, who used his explosives expertise to destroy countless villages, all in the name of the war. But after seeing so many innocent people's lives ruined by his actions, Chey began to question the purpose of the war and his role in it. Three years ago, he became the second person to desert the Fire Nation army and live. When he heard about Jeong Jeong, Chey went in search of him, hoping to gain some of his spiritual knowledge. Chey has been a part of Jeong Jeong's tribe for the last couple of years, trying to learn all he can from the great master, and gain enlightenment himself.(nick.com)

When Aang and his friends go to a Fire Nation festival, it is discovered that Aang is the Avatar, and the three friends quickly attempt to escape from Fire Nation soldiers. Fortunately, their escape is aided greatly by Chey. As they fly away on Appa, Chey explains he serves a Firebending master named Jeong Jeong who has abandoned the Fire Nation. Chey leads the group of three to Jeong Jeong's camp within a forest, but are intercepted by Jeong Jeong's followers. They are then led to camp, and there Aang attempts to try and learn how to firebend from Jeong Jeong. After the camp gets attacked by Admiral Zhao, everyone leaves. Chey had been in the forest and knew nothing of what had happened. Chey returns to the campsite only to find it deserted. What happens to Chey is yet unknown.