Yoon Do-Jin (Hangul: 윤도진) is a supporting character during Season 6 of the Netflix series Cobra Kai, being a supporting character in parts 1 and 2, a minor antagonist in part 2 additionally, and a minor character in part 3.
He was the former top student of Kim Sun-Yung's dojang and part of the newly revived Cobra Kai Dojo. He is portrayed by Daniel J. Kim.
He also starts four rivalries with Eli Moskowitz, Demetri Alexopoulos, Kenny Payne, and Vlad at the Sekai Taikai.
Cobra Kai
Season 6
Part 1
Yoon is the top student in Dohk Sa. According to Kim Da-Eun, his family has trained in the dojo for generations. However, he develops a rivalry with his rebellious classmate Kwon Jae-Sung. While Da-Eun is showing Kreese her students' skills, he demonstrates his skills by executing a defense technique that Da-Eun had her students master. Yoon and the other students at Kim Sun-Yung's dojang are present when Kim Da-Eun introduces John Kreese to the class. After being punished as part of a group punishment for Kwon's disrespect, Yoon, tired of Kwon's constant rebelliousness, berates Kwon and pushes him down.
Later in the night, Yoon is talking with two other students when he gets pushed by Kwon. He asks if Kwon hasn't had enough yet, then attacks him. Due to Yoon only knowing what he's been taught, Kwon easily takes him down. While Kwon is taking care of the other two students, Yoon kicks Kwon in the back and they continue fighting. Yoon is chopped in the neck by Kwon and beaten down as Kwon takes his patch as Yoon struggles to breathe and claims it for himself.
Part 2
He participates in the Sekai Taikai alongside his classmates. Early on, both he and Kwon are easily defeated by Iron Dragons captain Axel, and he is able to defeat Miyagi-Do student Hawk fairly easily. Later in the tournament, he takes on Miyagi-Do's Hawk, Demetri and Kenny, with the three tagging each other to tire him out. While he is initially able to fight all three on equal terms, he soon begins tiring out, which the three take advantage of by continuing to tag in and out, and stopping him from tagging out. Eventually, a tired and overwhelmed Yoon is defeated by Hawk, losing the point as a result. During the all out dojo brawl, he attempts to help Kwon beat up Robby, but the latter gains the upper-hand on both of them, and proceeds to get knocked out by Robby. And due to Yoon being unconscious, it’s possible he did not see Kwon get killed.
Part 3
Back in Korea, Yoon attends Kwon's funeral and watches as one of his fellow students lights up Kwon's casket on a pyre. Later, in class, he is ordered by Kim Sun-Yung to Forbidden technique on Chung-Hee and Min-Seok as punishment for Kwon's death. Yoon does so, severely injuring both students. Later, he is sent away by John Kreese in an effort to stop Cobra Kai from returning to the Sekai Taikai and to protect Yoon from Sun-Yung's brutality.
It is unknown if Yoon returned when Kim Da-Eun took over her late grandfather's dojang and started teaching her students her own way.
Personality
Yoon is described by Kim Da-Eun as a very dedicated student. He follows every order to perfection and always gives his best efforts to win a fight. Because of how disciplined and loyal Yoon is, he has also been shown to be one of the most polite and respectful Cobra Kai students ever seen. He is the only student in the Korean branch to actually be friendly to newcomer Tory Nichols.
Yoon was visibly hesitant when ordered to use the forbidden technique on his friends which, if he had mastered it, would've resulted in Yoon killing them. Even causing them great pain in his attempts clearly bothered Yoon.
Fighting Style
Yoon is a skilled martial artist trained in Tang So Do, the original style of Cobra Kai, which was later altered by Kim Sun-Yung. With a family legacy tied to the dojo, Yoon has likely trained since childhood, honing his skills through dedication and obedience to his senseis. He excels as a proficient fighter, earning recognition as Kim Da-Eun’s top student, and demonstrates mastery of complex techniques. However, his adherence to traditional teachings also renders his fighting style predictable, making him vulnerable to be defeated by opponents like Kwon who can exploit his lack of adaptability. This is further shown in the final elimination match between Cobra Kai and Miyagi-Do, where Hawk was able to pick up on Yoon’s repetitive striking combos and figure out how to counter them and defeat Yoon. His skills are also alot lower than the Iorn Dragons captain Axel, even with both's help they where both easily defeated in seconds in the opening round of the Sekai Taikai.
Despite this, Kwon calls him a formidable fighter to anyone else, which is backed up by his showings. Being able to gain the advantage and floor the skilled unbalanced Hawk early on, and later was capable of holding his own against Miguel Diaz for some time. One of his impressive showings is being able to fight Hawk, Demetri, and Kenny on equal terms, despite the three switching back and fourth during their tag team fight and stopping Yoon from tagging out. However, this eventually led to Yoon being overwhelmed and gassed out by the end, leading to him being defeated by Eli.
Ultimately, despite Kwon replacing Yoon as Cobra Kai's best student, Yoon proves to be second to none within his dojo. And with Kwon being dead, Yoon takes over again as his dojo’s top student, and trains specifically under Kim Sun-Yung in order to prepare for the tournament’s reopening. Because of this, Sun-Yung taught Yoon an ancient and forbidden Korean martial arts technique designed to kill an opponent, which effectively made Yoon a more dangerous fighter. However, Yoon was unable to master this technique before Master Kim Sun-Yung's death.
Yoon is considered to be one of the strongest teenage fighters in the whole current modern-day Karate Kid (Cobra Kai) universe, he is also above most of the teenage fighters such as Demetri Alexopoulos, Kenny Payne, Devon Lee, Wing, Shawn Payne, Min-Seok, Chung-Hee, Diego Aguilar, Draga, Maria Alvarez, Samantha LaRusso, Tory Nichols, Zara Malik, Piper Elswith, Aisha Robinson, Kyler Park, Brucks, Dre Parker, Cheng, Liang, and Wu Ping.
However, the only teenage fighters that can easily defeat him are Kwon Jae-Sung, Vlad, Eli Moskowitz, Axel Kovačević, Miguel Diaz, Robby Keene, Connor Day, and Li Fong.
Trivia
The spelling of Yoon Do-Jin's name in Cobra Kai is widely regarded as incorrect, as the name should be spelled, Yoon "Do-jin". In today's romanizations of Korean names, which are used by the United Nations, the Black Belt Magazine and other media, given names that consist of two syllables are spelled without capitalizing the first letter of the second syllable.
Despite this, The Karate Kid Fandom documents the franchise as it is seen and credited within the fictional franchise, not by what is considered factually accurate in the real world.
Yoon is the first student to have landed a hit on Axel Kovacevic before Robby and Miguel. He kicked him on the chest, initiating the fight between Axel, Sam and the Cobra Kai students, he then after gets effortlessly punched down by Axel. Although this hit doesn’t technically count, as Axel willingly took that hit to stand his ground; whereas with Robby’s and Miguel’s hits, Axel tried to block them, but failed.
Yoon was the only Korean Cobra Kai student who ever respected and was friendly to Tory during the Sekai Taikai.
Seeing that Yoon is not amongst his classmates training in the final episode of Cobra Kai, it is unlikely Kim Da-Eun tracked him down and brought him back to her dojang or she has not done it yet.
Despite being a Cobra Kai in Season 6 Part 2 and typically joining Kwon in taunting the Miyagi-Do students, Yoon cannot really be seen as an antagonist considering each of his antagonistic actions come from the manipulation of his allies. He, along with Kreese, learns from Kwon’s death, and leaves Kim-Sun-Yung’s dojang at Kreese’s discretion, redeeming himself.
