Kage no Dansu(sword)

Kage no Dansu is a legendary sword forged for, and wielded by Tsuki Aya. The sword can cleave through illusions, souls, and even dreams. It is virtually indestructible, as there is no way to destroy it with any object. However, when infused with Death's tears and the Oblivion Sphere, it gains the ability to reset a dimension to a time of life. This ability is to ensure that the Celestial world could be revived in the event of extinction, in which Aya, the only immortal angel, could reset the world, restoring all life on the planet to the time just before the catastrophe, causing the event to never take place. It is also capable of cleaving through dimensions, shown when Aya managed to escape the banishment dimension into the revitalized Earth in Banishing Light.

Its name means 'Shadow Dance' in Japanese.