Mai-Otome

One year after the defeat of Nagi, a powerful new enemy threatens the world, turning its victims into stone. While Meister Arika is ready to protect the people, an argument between her and Queen Mashiro could prove to be her undoing, as it prevents Arika from tapping into her Materialize Zwei form. During a battle, before Mashiro and Arika can settle things, the Black Valley disappears and with it Mashiro and Mai.