Water. Earth. Fire. Air. Long ago, the Four Nations lived together in harmony as the North & Southern Water Tribes; Earth Kingdom; Fire Nation, and Air Nomads. Then, everything changed when the Fire Nation attacked. Only the Avatar, master of all four elements, could stop them and return balance to the world, but when the world needed him most; he vanished. A hundred years after the war began, a young Firebender by the name of Kion discovered the new Avatar: The Last Airbender named Aang. The two soon met Katara and Sokka of the Southern Water Tribe as well as self-proclaimed greatest Earthbender in the world, the Blind Bandit: Toph Beifong. Together, the five traveled the world, stopping the Fire Nation whenever they could while training Aang in mastering the elements. Team Avatar quickly learned that defeating the Fire Lord and Nation were not their only obstacles as A group of "Freedom Fighters" as well as a run in with Pirates proved they had more enemies then one. The Fire Nation's prince and princess Zuko & Azula were also after them to capture the Avatar and stop the only threat to their father.
The group all had their own backstories and reasoning to fight in the war. Aang was not only the Avatar, but the Last Airbender; Katara and Sokka had lost their mother in a Fire Nation raid, while after living a sheltered life, Toph decided to run away from her home life and joined the Avatar to be his Earthbending teacher. Kion, however, didn't come from a tragic past or backstory that fueled him. He didn't see it that way, at least. His parent's had both died when he was an infant, never truly knowing them, nor was he ever adopted into a new loving family. As such, he grew up to resent his own nation and was ashamed to call himself a Firebender as it was his Nation responsible for sending the world into a chaotic war. Over the years, Kion did everything in his power to stop the Fire Nation. He had freed small Earth Kingdom towns, while even playing as bodyguard to small Water Tribe villages whom had never been apart of the war. He also caused havoic to his own Nation. His lifestyle as well as his unique firebending abilities granted him the nickname of the "Blue Spirit" as his firebending was of blue electric flames. Azula of the Fire Nation was the only other known bender to have her bending on such a level high enough to produce blue fire. Kion, however, took it a step further. Just as Toph became the first Metalbender, Kion spent most of his earlier years perfecting the "cold-blooded fire" which was most commonly referred to as Lightning. It was common knowledge that Firebenders could not control it; they simply separated the two energies and acted as a guide once the lightning was created. Kion was able to tap into his own chi enough to create and control it. Fire he created was always electrified with static electricity and during storms he could even control and bend natural lightning as well as direct it.
Having fought and defeated Zhao at the Northern Water Tribe, the group made their way to the Earth Kingdom which is where they befriended Toph who served as Aang's bending teacher alongside Kion and Katara. That particular day had been proving to be uncommonly laid back for the group. Usually, they were on the move with Zuko & Azula or some other villain behind them. But today, they were actually getting to enjoy some relaxing time in a nearby valley. The setting was perfect for Aang to practice Earthbending, while further down the valley was a beautiful oasis Katara would take him for his Waterbending and there was also a more secluded spot that Firebending could be practiced safely.
Kion's appearance masked that he was actually Fire Nation. His outfit consisted of a long dark violet cape with a black sleeveless tank top under it and beige pants. He wore golden armbands and bracelets as well as an metallic silver lightning bolt pendant around his neck. His hair was long, falling to about his lower back in length and was a dark ebony black with hues of blue reflecting from it. Asides his bending, the only thing that did give him away the most was his hair was usually pulled up into an Fire Nation styled ponytail or bun. Although he was a firebender, his reputation as the Blue Spirit was known and he was often recognized and greeted just as Aang was as the Avatar. He assumed people looked to him just with as much hope being he was a Fire Nation rebellion. What he was most impressed by was just how much Aang had grown as an Avatar in the several months they had known each other. Kion would have never thought after finding the boy frozen in ice that the two would have actually grown to be quite close. The two had shown a lot of loyalty and trust to one another and even a certain "spark" something Toph often could sense due to her unique bending style and would tease the two playfully. Kion didn't mind it much, and he enjoyed seeing Aang so flustered and embarrassed by it. Although never talked about, the two knew there was some sort of a connection between them. Something, Kion could not figure out. Maybe it was destiny that he found Aang? Only time would tell.