Ancient Sky Book

Link was given the Ancient Sky Book by Impaz in the Hidden Village during the events of the Twilight Princess. It was used to translate the strange language of the Ooccoo. Link used it specificaly to translate the Sky Characters on Owl Statues hidden around Hyrule so he might gain access to the City in the Sky. But before he could use the statues, Shad had to use the Sky Book to recharge the Dominion Rod.