|"The spirit's name is Koh, but he is very dangerous. They call him the Face Stealer. When you speak with him, you must be very careful to show no emotion at all. Not the slightest expression, or he will steal your face."|
|— Roku to Aang about Koh.|
Koh the Face Stealer is one of the most ancient and knowledgeable spirits in all of the Spirit World. He is a malevolent entity with the body of an enormous centipede-like creature and resides under an ancient tree in the Spirit World. His self-chosen name reflects his ability to literally steal the faces of other beings who express emotion and use them at will by "blinking".
Koh was born to the Mother of Faces thousands of years before the Hundred Year War. Over time, he increasingly interacted with the human world and started to carry out punishments against perceived wrongdoers as well as answer questions to those mortals brave enough to face him. The latter behavior resulted in some discontent among more ancient spirits such as Father Glowworm, who believed that Koh set a bad example by allowing any human to approach him.
When Ummi and Avatar Kuruk were getting married, Koh lured Ummi to the Spirit World, where he stole her face and trapped her forever as punishment for Kuruk's arrogant ways. Kuruk was determined to end Koh's life but when he eventually met the spirit, he could not go through with it as Kuruk realized that killing Koh would also destroy the love of his life. Despite Kuruk's vindictive actions, Koh himself held no personal grudge against other Avatars, as they were different incarnations.
Aang appealed to Koh for information regarding the Moon and Ocean Spirits, Tui and La, when Koh warned the Avatar of impending danger the spirits faced. Aang asked for their location in the mortal world, but the spirit would not provide a clear answer and merely stated that they were opposites, forever revolving. When he told Aang that the boy had already met the spirits, the Face Stealer barely missed Aang's expression of epiphany when he realized that the identities of Tui and La were the koi fish in the Spirit Oasis.
Before Aang left, Koh stated they would meet again, which they did when Aang found himself in the Spirit World after being struck by Azula's lightning in the Crystal Catacombs of Old Ba Sing Se. During that encounter, Koh attempted to steal the young Avatar's face before he reconciled with the other past Avatars but failed.
Koh is a perilous force who can be dangerous to meet. He possesses a sadistic personality and constantly tries to goad the slightest bit of emotion out of his visitors, even if it is the Avatar, by frightening them with his monster-like appearance or taunting them with his many faces. However, Koh's actions suggest he is amoral rather than purely evil; he stole Ummi's face to punish Avatar Kuruk for his arrogance, but willingly told Aang the names and location of the Moon and Ocean Spirits and the danger they were in, as well as leading the young airbender to his past Avatar lives. He also is cryptic and often speaks in riddles. Another spirit, Father Glowworm, derogatorily described Koh as "chatty" due to his readiness to talk with humans.
Koh has the ability to steal the face of anyone or anything that shows even the slightest emotion to him, which is why those who are aware of his power attempt to remain inexpressive while in his presence. Stealing an entity's face will not kill them, as proven by a faceless monkey living outside his lair, and Rafa, another victim, did not require food or oxygen, though his victims will enter a state "somewhere between life and death" that can persist for years.
Koh has stolen over millions of faces during his lifetime, of which only a few are known:
- A female Noh mask, a white face with red lips and gray eye markings. This was the face that Koh wore most often.
- A curly-tailed blue nose face from the faceless monkey Aang found outside Koh's lair.
- Ummi, a Southern Water Tribe woman with long wavy brown hair and brown eyes, who was the fiancée of Avatar Kuruk.
- A bearded and mustached man's face. This is based upon another Noh mask.
- An owl's face with light brown feathers and emerald green eyes.
- A blue oni face, reminiscent of the Blue Spirit mask worn by Zuko. Koh shifted to this face when expressing extreme emotion.
- An old man's face with a white mustache and blue eyes. This is another mask used in Noh theater.
- A young man's face with brown hair and gray eyes. He was a Fire Nation soldier.
- Rafa, the brother of Misu, as punishment for his misdemeanors. This was negated years later by the Mother of Faces.
|Mother of Faces||
Avatar: The Last Airbender
Book One: Water (水)
Escape from the Spirit World
- "Chapter 1: Avatar Roku"
- "Chapter 2: Avatar Kyoshi"
- "Chapter 3: Avatar Kuruk"
- "Chapter 4: Avatar Yangchen"
Book Three: Fire (火)
- 319. "Sozin's Comet, Part 2: The Old Masters" (flashback, no lines)
- Nearly as old as the Ocean and Moon Spirits, Koh is among the few known entities to remember them crossing over to the physical world, where they took the forms of koi fish.
- Koh is much younger than some other spirits, who consider him a mere "upstart".
- Koh chose the name "Koh" for himself after becoming distanced from his mother, the Mother of Faces, though legends say that, despite their strained relationship, he steals faces as a way to be close to his mother, who has the ability to give faces.
- Gene Luen Yang, who considers Koh to be "one of the best villains ever created", wanted to find a way to include him in The Search due to the trilogy's prevalent theme of faces, thus making him happy to connect Koh with the Mother of Faces.
- His name resembles the Japanese word kao (顔, かお), which means "face".
- Koh stated that he stole Ummi's face "nearly eight or nine hundred years ago", when in actuality Avatar Kuruk lived only about four hundred years before. However, it is known that time passes differently in the Spirit World.
- Koh shares similarities with the Noppera-bō, a supernatural Japanese spirit or yōkai that was known for stealing the faces of other people.