Zanto was the second-born son of a mild noble house in the fire nation. His mother was an air nomad who died giving birth to him. His father Ikem raised Zanto and his older brother Zakari with harsh discipline, and when old enough rigorous training. He was a fourth generation military man and fully expected both of his sons to follow in his footsteps. Zakari took right to the training and expectations, growing up the perfect soldier: Big, strong, talented, and smart enough to be competent but without asking too many questions. Zanto, on the other hand, grew up much different. He was fairly strong for a kid his age but nothing compared to his brother. Where he excelled was bending, showing great technique and immense power. But his drawbacks were his temper as well as his tendency to challenge authority. The two combined often got him in trouble with his masters, father, and superiors.
Superior - "Zanto, you are learning explicitly how to start a campfire without firebending! Do it again and do it right!"
Zanto - "Why? In what situation would I not be able to firebend but I would have access to mundane fire making equipment?"
The questions were often well meant, but taken the wrong way and Zanto's hot temper quickly turned the situation worse. His father would always tell him, "You're so talented, you wouldn't be such a disappointment if you just did what you were told." As Zanto grew to be a teen his rebellious nature only got worse, and finally he quit his military training programs. When his father learned he disowned Zanto, leaving his clothes and a note outside their house for him to return to. Furious that his father wouldn't even consider other options Zanto fled the fire nation and the chains his family had put on him, finding a ship that he worked on in exchange for passage.
The ship took Zanto to the western air temple, the birthplace of his mother. He wanted to learn more about the other side of himself and decided to live amongst the air nomads until he figured out what to do with himself. The culture there was perfect for him. It both gave him the freedom to pursue his interests as well as an environment and wise old nomads who helped to calm his temper, although he still remained easily roused to anger. One of his favorite activities was sparring with the airbenders there, who took such a different approach to combat than his firebending peers and masters. Firebending was all about striking with as much force as possible with little thought for self defense, but the airbenders were nimble and weaved around his slow, powerful attacks.
This led Zanto to study airbending and it's techniques, his competitive nature wanting to be able to best the quick little nomads. It was during this time that came upon one of the ancient journals of Avatar Yangchen (who was born in the western air temple). As the Avatar she often observed the relationships between different elements, and in one of her notes wrote "...it was the very air that was flammable, the oxygen around us..." Zanto was enthralled by the idea, so instead of creating fire from his own chi he tried superheating the air with his chi in an attempt to light the flammable particles already there. It was a hard process that took many months of hard work with little results. He discovered that while oxygen may be flammable, the kind in the air's structure wasn't well suited for his purpose. He was in his room one day and tried using firebending to excite the particles and change their structure, then quickly met very violent results. His experiment succeeded catastrophically, blowing up half of his room and nearly severing his nose from the resulting debris. Once he got over the shock he smiled and laughed, knowing that he had discovered something much more significant than a trick to fight fast opponents.
The air nomads were mildly excited about his discovery, but also wary of the bending technique's raw destructive power. From the years of Zanto's life spent at the temple they knew he could be a loose cannon but had a good heart, so they decided to focus his energy on a good cause: The Order of the White Lotus. He was introduced to the local Grand Lotus who told him about the ideals of the order. Zanto loved the idea of an organized group that promoted peace and truth, so he jumped at the opportunity to find a calling that sat well with his wild heart.
