Background
Hakon (pronounced Hakin) was born in Nyarri from a noble family. He knew local nobles like Alev. Hakon's father was a successful painter, and his mother was known for hosting high-profile events. He was the same age as Kett (17) during the second book of Avatar: Macai's Journey and the first two books of Avatar: The Last Airbender.
Personality
Hakon was very focused whenever he was working on the job. He didn't joke, laugh, or play around a lot before missions. Hakon saw his job and missions as duties of the utmost importance meaning there was little time for childish banter. Before his tournament match with Kanna, he ignored her pre-fight banter. Hakon preferred to stick to routines and hated improvising.
Hakon wasn't particularly arrogant or flashy. He had a strong sense of honor, but Hakon's honor was accompanied by a unwavering loyalty to his nation. This was a big difference between him and Zuko, because Hakon would not hesitate to obey orders. According to Hakon, honor did not exist without loyalty, and it was up to the leaders of his nation to define the terms of honor that subjects should abide by.
Abilities
Hakon was one of the most skilled firebenders in Nyarri. Before the Nyarri Tournament and Macai's arrival, he was ranked number 2 for promising Nyarri benders after Alev. Hakon cared deeply about his troopers, was a sound strategist, decent tactician, and someone who preferred to stick to routines.
Hakon had a balanced fighting style that combined offense with defense. Still, he usually preferred to fight from a greater distance than most firebenders. His flames had a cherry red exterior and a white interior. This made his flames equally hot to the average orange and yellow flames. Hakon's flames were incredibly combat, his attack precise, and his movements sharp. Hakon often picked his enemies apart, had a higher attack output than more counter-offensive fighters like Azula and Kanna, but also had a lower output than brawlers like Prince Zuko (before he was met the Sun Warriors).
Hakon often placed initial attacks to set up new attacks. His timing was elite, but his brawling skills weren't as impressive. Because Hakon was a very clean fighter, he often preferred to keep skilled opponents from getting too close. When it came to less skilled opponents, they rarely lasted long enough to get close.
Hundred Year War
Hakon enlisted in the military during the last two years of the Hundred Year War. Hakon won several small and mid-scale battles against the Earth Kingdom as a Lieutenant in the Army. He quickly moved up in rank to a Captain before Avatar Aang was discovered by Prince Zuko. Halfway through that year Hakon was promoted to the rank of Major for his obedience, loyalty, and ability to shut down a major surprise attack from Earth Kingdom and Water Tribe forces.
Fire Nation Remnant
After Ozai's Administration was overthrown and Zuko became the new Firelord, several Fire Nation military members rejected the change. Hakon refused to serve a leader that he felt illegitimately took reign of his country. Hakon believed Zuko had to defeat Ozai to gain the throne and questioned the validity of his Azula Agni Kai considering her faulty mental state. Hakon fought a well-planned out guerrilla war against Zuko's administration.
Due to a lack of leadership, Hakon was promptly promoted to a Colonel in the Fire Nation Remnant. He was initially overwhelmed by his increased leadership responsibilities. Soon after, Hakon was able to adjust but only performed effectively as a colonel and started to use novel strategies to undermine Zuko's administration while hardly being noticed.
Through his wits, patience, and humility he managed to evade capture and death from the Fire Nation military. Even leaders like General Mak and Commander Macai were not able to locate or route out Hakon during the first two years after the Hundred Year War. After a disastrous campaign that led to the death of thousands of Remnant troopers, Hakon briefly retired from his role. He became an alcoholic until Fire Nation Remnant members Ronin, Kedo, Alev, and Gendall helped Hakon regain his inspiration. However, his lucky would eventually run short after a planned Depot Raid led to a clash where Macai, Azula, and his old rival Kanna were present.