Xiam is a secret Nobody that was made during Sora and Riku's journey through Castle Oblivion. Zexion found her, and helped her learn about where and what she was. Bearing a mace and one of Zexion's lexicons, Xiam controls the Pearl element, a different element in which the King also can - interestly enough - control. When the two remaining Nobody organizations learn of Organization XIII's return, they team up to learn the dirty secrets they hold.