Sleeping Beauty is a strange tree that shows dreams of death to the inhabitants of the Forest of Myth. Its true identity is that of a huge network computer that runs on the demonic element and it drops hints suggestively telling of truth. It works to keep the web of memories that has been torn apart following the destruction of the world.
Completing the puzzles the tree gives you rewards you with the "Tree of Memory" key to the Shadowlord's castle.
Its name comes from the fairytale “Sleeping Beauty”.
During one of the dream puzzles, it says, "Look at my memory. A red dragon falls from the heavens... Ah, that memory has been lost. A shame. It was a favorite of mine...". This is a reference to the Red Dragon from Drakengard in Ending E.