Crystal Stars

The Crystal Stars are the 7 objects Mario, Goombella, Koops, Flurrie, the Yoshi Kid, Vivian, Bobbery and Ms. Mowz collect in Paper Mario: The Thousand Year Door. They open the Thousand-Year Door to the Palace of Shadow and will teach Mario 7 special moves. They consist of the Diamond Star, the Emerald Star, the Gold Star, the Ruby Star, the Sapphire Star, the Garnet Star and the Crystal Star.

The stars where created by the Shadow Queen to hold the essence of the heavens, but the four heros collected them and used their power against the Queens. One of the castles built to hold the stars is Hooktail Castle.