Before the Great Deku Tree dies , he gives Link the Kokiri Emerald , a magic stone , and tells him that it was a man in black armor who put the curse on him . He also tells Link that he needs to go to Princess Zelda of Hyrule at Hyrule Castle . Before dying , the Great Deku Tree gives Link the spiritual stone of the forest , the Kokiri 's Emerald , and sends him to Hyrule Castle to speak with the princess of destiny , Zelda .