Ancient Sky Book

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Location and Uses
The Ancient Sky Book is a book received from Impaz at the Hidden Village after showing her the deactivated Dominion Rod. It is the key to restore power to the Dominion Rod and reach the City in the Sky. To achieve this, Link must find all six missing Sky Characters hidden beneath the Owl Statues scattered across Hyrule after Shad restores power to the Dominion Rod.

Sky Characters are symbols that makes up the written language of Sky Writing,  which forms the basis of the ancient language of the Oocca.