"Hi! Do you think my face is kind of plain?"
Introduced in The Legend of Zelda: Ocarina of Time, Skull Kids are impish creatures that live within the mysterious Lost Woods. Unlike the monsters of the forest, Skull Kids don't appear to be evil, merely mischievous. They are said to have once been children who wandered too far into the forest and were transformed by the forbidden air. While their trickery can tend toward cruelty, in the end they've helped Link, the Hero of Time, on his quests more often than hindered him. It's only when they come into contact with adults that they turn violent, displaying a childlike fear that is the last remnant of their former lives.
One Skull Kid in particular formed a friendship with Link, happily trading music and masks with him whenever the hero returned to the woods. What began with a chance musical jam, however, would later force Link to undertake a quest in an alternate world closely related to his own: Termina. In The Legend of Zelda: Majora's Mask, the Skull Kid ambushes a wandering salesman and steals a mask of great evil. Known as Majora's Mask, it subtly takes control of the Skull Kid, negatively influencing his personality and granting him access to dark magic, which he uses to pull down the moon from the sky in order to destroy the world. He also waylays Link, stealing his possessions and later transforming him into Deku Link. Although the people of Termina, and Link himself, have reason to fear and hate the Skull Kid, his fairy friend Tatl maintains a different perspective. She believes that the mask completely possessed the forest imp, deepening the anger and loneliness he felt after some of his closest friends abandoned him one night and didn't come back.