Merlin is the son of the earth, the sea, the sky. Magic is the fabric of this world and you he was born of that magic. He is magic itself. The heart of the Crystal Cave reveals Merlin's true self. He comes out of the cave as Old Merlin (for the first time aged up without the help of a potion, and old man for real) wielding a power he can not master or conceive of as a young man and ready to fulfill his destiny.