The Sun Warriors are a secret legendary tribe who are the founders of The Fire Nation. Their chief was Phoenix Feathers on his headdress for it is the bird of fire since it burns into flames during death and are reborn from their ashes. Iroh told the Warriors that he'd lied to the rest of the nation that he killed the last two Dragons to keep them safe. Later on Zuko and Aang were on their way to find the origins of Fire Bending and they first thought they were intruders. But when they learned that they came to them to understand the true purpose of the element Fire they had them perform the Dragon Dance and The Chief said that they judged them. Aang than said all his life since The Fire Nation tried to capture him he thought Fire was destruction and since he burned Katara he was stressed and didn't want to learn it. But then he realized why it's one of the four elements and why he needs to use it because it's energy, healing, resurrection and life! Zuko to realized that its like The Sun since it's a giant star that holds all the galaxy's planets in its gravity field. They then understand why they're called The Sun Warriors since the were the founders of The Fire Nation for it is the first of the 4 elements and the first nation. Aang and Zuko thank them for teaching them and they promise not to tell anyone that they're still alive.