|Occupation||Elder of the Wind Tribe|
|Relatives||Hak (Adopted Grandson)|
Tae-Yeon (Adopted Grandson)
|Manga Debut||Chapter 03|
|Anime Debut||Episode 03|
|Japanese Voice||Katsuhiko Sasaki|
Son Mundok (ソン・ムンドク Son Mundoku) is the former General and leader of the Wind Tribe. He is the adoptive grandfather of Hak and Tae-Yeon. Before his retirement, he was known as a general whose strength was on par with General Yu-Hon’s.
Mundok is an old man with blue eyes. He has a long scar etched over his right eye that made his eyelid shut permanently. He ties his grey hair in a ponytail and is wrapped with an umber brown bandanna on his forehead. On the sidelocks of his fringes, there are beaded ornaments decorated on each ends. He also has a grey mustache and beard.
He wears a blue robe held by a brown sash under a brown overcoat with patterned dark brown hemlines. For his footwear, he dons a pair of dark brown loafers.
Despite his strict demeanor and appearance, Mundok cares for everyone who lives within the Wind Tribe and the royal family, whom he shows deep loyalty with. He has a strange tendency to not abandon orphans, which resulted in the adoption of his two current grandchildren: Hak and Tae-Yeon. Mundok is also very sharp, especially when it comes to matters of political intrigue, and does what he can to protect his own while dealing with the matters within the courts.
He took in Hak, an orphan, as his own grandson and trained him to be a warrior. He has also taken in Tae-Yeon, another orphan with a weak body.
Mundok and the other generals are summoned to Hiryuu Castle for an urgent meeting regarding the incident that happened to the royal family. Hak is also missing and suspicions that he killed Emperor Il rise against him. In the meeting room, the Fire Tribe General, Kan Soo-Jin, accuses him for treason in a possibility that Hak betrayed the emperor. Mundok denies his claim while the other two generals remain neutral on the issue. Soo-Won, Han Joo-Doh and Kye-Sook arrives at the room and dissolves their tension. Along their talk about the kingdom’s future, Soo-Jin points out the need of the new king, and Kye-Sook quickly suggest Soo-Won for the position. Every general agrees to the proposition except for Mundok, saying that he is too tired and should be discussing this issue to Hak instead. He stands up from his seat and is about to leave, however, Soo-Won asks him what he can do to gain his approval. Mundok answers him that if he is to marry Yona, he will have his compliance and will even present him with a gift. He also adds that he believes that his grandson will not leave the castle without reason. Soo-Won, while still going easy on him, advises him to reconsider his decision for the sake of Fuuga’s people. Hearing this, he outright tells him how he also thought of Soo-Won like his grandchild and leaves.
He returns home to Fuuga and sees Hak together with Yona. He hugs Yona and apologizes that he is not able to help her during the time of her father’s murder. After that, he greets his grandsons until an injured Han-Dae come back from his investigation. Mundok learns that the Fire Tribe blocks the waterway to their river and some of his tribesmen grow mad. He calms them and asks Tae-Woo to assist Han-Dae to the infirmary. He states to Yona and Hak that the Fire Tribe is starting to pressure them as they want to make Soo-Won a king. Seeing Yona tremble, he assures her that he will not accept Soo-Won’s ascension to the throne because if he does, it is like he accepted that Hak is a murderer. He promises her that he will do his best to prevent the Fire Tribe for causing any more damage.
That night, Tae-Yeon suffers an asthma attack and the merchants who are supposed to bring his medicine were attacked by the Fire Tribe. Mundok remains quiet on the pleas of his men, but Han-Dae appeases their anger with his plan to get a medicine from a doctor on the east forest of Fuuga. Hak follows Han-Dae’s example and calmly commands everyone to have them trust him on their situation. Because of this, Mundok relaxes and sees his men to be lively. Following that event, Mundok is busy reading at his room when Hak visits him. His grandson offers him a bottle of sake and they talk about his plan of leaving the Wind Tribe for good and about Yona’s future. Hak asks him to accept Soo-Won’s coronation for everyone’s sake. He also returns his name “Son” to him and asks him to let Yona stay at Fuuga as a Wind Tribe citizen for the rest of her life. However, Mundok declines his request and stubbornly tells that he will only follow it if Hak is to order him as their chief. Hak agrees to his demand and orders him to do what he said. By that, Mundok accepts his order as he sheds a tear.
The following morning, he hides himself at the entrance gate as he watches Hak trying to make Yona stay at Fuuga when he is leaving. When his grandson eventually gives up, he shows up with a bow and arrow on his hands and aims at Hak for his behavior. He then turns to Yona and states how he is losing another grandchild. Yona denies it as she tells him that she is a part of his family. Mundok advises her that when she needs help, she can always ask the Wind Tribe for assistance. Before the two leaves, he tells them to seek the guidance of the priest living somewhere at the tribe.Days later, he attends Soo-Won’s ceremony together with their new general, Tae-Woo. During the event, he asks Soo-Won what he will accomplish during his reign as he needs to know so that he can convey to the past Emperor Il about it when they meet in heaven. Soo-Won answers him coldly and witnessing the expression the new king has in his face, Mundok thinks that he will never see his kind and gentle smile again.
During flashbacks and the current story, it is shown that Mundok has a love-hate relationship with Hak, like any family would. He often requests Hak to call him "Grandpa" or hug him, much to Hak's displeasure and denial. However, he is strict with his grandson when the occasion arises, especially when he becomes disrespectful to the royal family.
Mundok has a very doting relationship with Yona, often paying his respects to her when meeting in person and hugging her. He also considers her like a grandchild to him, and tearfully hugs her upon learning her survival.
Like Yona, Mundok has always thought of Soo-Won as his grandchild. However, after the events of Emperor Il’s death, they have a strain relationship and he has come to the conclusion that things won't go back to the way they once used to be. Because of this, he is sad that he won't be able to see his gentle smile again.