The Sound PrismEdit
The sound prism is an ancient sphere made to call the Homunculus. When you throw it in the air, it makes a mystical sound that, when the notes are revealed, spells out "Cabbage Face". When you turn it, it also reveals a poem that, once solved, tells the reader the name of the Jester. The prism also lets you hear things that you would otherwise be unable to.
It last resided in the Magic Museum, until the Midnight Sun stole it for their own purposes. They wanted it to call the homunculus, who at the time guarded Lord Pharaoh's grave. They thought that in his grave they could find a clue to the Secret. It has also been previously owned by the Jester when he worked in the King's court and many of his descendants.
Max-Ernest and Yo-Yoji used it to listen in on where Cass was and saved her. They also used it to create an avalanche and thus create a distraction that would enable them to go save her. The three then returned it to Pietro where it lays in the Magic Museum.