|"Greetings, enemies of Kunyo! Prepare to be roasted in the flames of your own defeat!"|
|— Kunyo to Toph and her students before their duel.|
Master Kunyo was an experienced firebending instructor who started as Prince Zuko and Princess Azula's master. He was eventually banished to the Fire Nation colonies by Prince Ozai after Azula told her father that Kunyo was a horrible teacher, even though Zuko held him in high regard. In the colonies, he ran Master Kunyo's Firebending Dojo near the city of Yu Dao before the Harmony Restoration Movement started the decolonization process by which he lost his property. After a short-lived attempt to retrieve it, Kunyo was forced to transfer the ownership of his dojo to Toph Beifong for good.
Kunyo was designated as Zuko and Azula's teacher. In 94 AG, during a lesson, he told Azula that one of her forms was incorrect, saying she was holding her arms too far apart. The young princess asserted that her stance would result in the biggest fire blast, but Kunyo told her to do the form his way, which prompted Azula to set his pants on fire. When his daughter told then-Prince Ozai this story, the prince said that Kunyo sounded "like a fool" and ordered him to be sent to the colonies. Zuko tried to defend Kunyo, but was silenced by his father. He eventually settled in Yu Dao and started a new dojo.
Due to the effects of the Harmony Restoration Movement, Yu Dao started the process of decolonization, and Master Kunyo was forced to give up his property and transfer it to Earth Kingdom ownership. The building in which his school was located was confiscated and sold to Toph Beifong, who transformed it into the Beifong Metalbending Academy. However, after Fire Lord Zuko withdrew his support for the movement in 101 AG, Kunyo returned with his three students to reclaim his property. When he arrived back at the building, only Ho Tun, Penga, and The Dark One were present, and he easily managed to drive them out of the school. However, right after he had reclaimed ownership of the building, Toph returned and proved to be a much tougher opponent than her three students. Kunyo laughed at Toph when he found out that she was teaching metalbending, as he thought that it was impossible, a mere fantasy. However, Toph proved him wrong by metalbending one of the spears that served as wall decoration around his head. When the two sifus were about to battle for the right for the school, Sokka halted them and proposed to let their respective students fight it out instead of the masters as they would have effectively destroyed the entire building. Kunyo agreed to Sokka's "battle to the sit" proposal, as opposed to a "battle to the death", which meant that the first team of students that managed to make another student sit down was victorious. Kunyo left the school to be back for the face off in three days, but not before giving them the "Kunyo salute", an acrobatic move demonstrating his students' abilities.
On the day of the battle, he returned to the academy full of confidence; however, he had been unsuccessful in removing the bent spear from his head, which Sokka mocked him for, so he had decorated it with two flags, one sporting the firebending elemental symbol, and the other one sporting his school's symbol. He appeared to have won back his school when a hopeless Toph surrendered. However, her attempt to sit down and surrender was thwarted when her metalbending students came back to the facility trying to stop her, as Ho Tun suddenly metalbent a coin. Aggravated, and presuming this to be a "dirt people trick", Kunyo ordered his disciples to attack, but he found that their firebending was useless against the metal coins of their opponents. Nonetheless, Kunyo demanded that his disciples continue firebending, until he was knocked on his face when he was hit multiple times with several of these coins, causing him to fall sat down and lose the battle. Defeated, he walked away, supported by his students, re-allowing Toph control the academy.
Kunyo did not give up, however, and sent an official complaint about a "dirt girl" - Toph - and a "snow savage" - Sokka - taking over his school to his former pupil, Fire Lord Zuko. Nevertheless, his complaint was ignored, since the Fire Lord was about to fight a new war and had no time for such matters.
Master Kunyo was a hot-tempered man with an arrogant and theatrical manner. Conservative in his training methods and world view, the firebending instructor was a firm believer of the old Fire Nation ways, including a strong disapproval of other bending arts and cultures. Because of his obstination, Kunyo refused to back down even when wrong, as evidenced when he decided not to remove the spear that Toph had wrapped around his head with metalbending, instead decorating it with Fire Nation banners. Proud of his Fire Nation ancestry and firebending ability, even looking down on other benders, Kunyo transmitted his thoughts to his students while training as a way of encouragement. In fact, his attitude toward people of other nations, for example to call those from the Earth Kingdom "dirt people" and those of Water Tribe heritage "snow savages", bordered on racism and mockery.
Though authoritative, he proved to be a very effective teacher. Before his banishment, Kunyo's reputation was high enough to be appointed as Azula and Zuko's firebending teacher, and even Sokka and Toph were impressed by the abilities of his very young students. Nevertheless, because of his conservatism, Kunyo was convinced that good firebending was based on traditional forms and hard training, not creativity or emotionality. This attitude eventually led to his exile, as his views conflicted with Azula's personality. After trying to lecture her, the princess achieved Kunyo's banishment as retaliation.
He usually showed a no fear attitude when confronting his opponents, and he taught his students to do so. This attitude was clearly noted when they all were willing to fight a 'match to the death' with Toph's students.
- The Promise trilogy
- Kunyo's physical appearance is based on that of actor James Hong.
- Kunyo is written as the embodiment of colonialism, its antagonism, and its inhumane acts toward others. Colonizers, Yang says, "deserve to get their butts kicked." Although the novel does delve into the higher complexities of colonialism, the message of the decimation of Kunyo by his enemies is simply that "the colonizer gets his butt kicked."
- DiMartino, Michael Dante; Konietzko, Bryan; Yang, Gene Luen (writer), Sasaki of Gurihiru (penciling, inking), Kawano of Gurihiru (colorist), Heisler, Michael; Comicraft (letterer). The Promise Part Two (May 30, 2012), Dark Horse Comics.
- DiMartino, Michael Dante; Konietzko, Bryan; Yang, Gene Luen (writer), Sasaki of Gurihiru (penciling, inking), Kawano of Gurihiru (colorist), Heisler, Michael; Comicraft (letterer). The Search Part Two (July 10, 2013), Dark Horse Comics.
- DiMartino, Michael Dante; Konietzko, Bryan; Yang, Gene Luen (writer), Sasaki of Gurihiru (penciling, inking), Kawano of Gurihiru (colorist), Heisler, Michael; Comicraft (letterer). The Promise Part Three (September 26, 2012), Dark Horse Comics.
- DiMartino, Michael Dante; Konietzko, Bryan; Yang, Gene Luen (writer), Sasaki of Gurihiru (penciling, inking), Kawano of Gurihiru (colorist), Heisler, Michael; Comicraft (letterer). The Promise Library Edition (February 20, 2013), Dark Horse Comics.