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A female recurring character in The Legend of Zelda series. She is a descendant of the mysterious Sheikah tribe that has served the Royal Family of Hyrule for many generations, and is Princess Zelda's personal attendant. She often aids Link in his quest by giving him useful information. Her depiction in each game has varied widely; from a withered old woman, to large, middle aged woman, to a lithe, young bodyguard.
In Ocarina of Time and A Link Between Worlds, she is the Sage of Shadows.
She returns as a playable character in the spin-off title Hyrule Warriors, where she fights using a giant blade and a naginata. Ironically, she is initially suspicious of Sheik.
The Impa in Hyrule Warriors: Age Of Calamity is the exact same Impa as the one in Breath Of The Wild, except a hundred years younger. This Impa is much closer to Paya, her future granddaughter, than to any previous versions of Impa, and not just in looks.