The Prince of Elfheim, also known as the Elf Prince, is a minor character from the original Final Fantasy. He resides in a castle at Elfheim and is put into a deep sleep by the evil dark elf Astos. The Warriors of Light find Astos and defeat him, and later use a special potion, the Jolt Tonic, created by Matoya to revive the prince, who gives the heroes the Mystic Key.