Dresden Slate

The Dresden Slate is a mysterious stone that appears to be the source of the Auras and various Swords of Damocles used by the kings.

The power of the slate could manifest not only in humans but in animals as well.

History
Little is known about the Slate other than that it was a subject of Germany’s research during World War II, with its tests lead by researcher Adolf K. Weismann. After the bombing of Dresden, Daikaku Kokujōji brought it to Japan, where it is currently in his possession.