Once upon a time, a dragon, nicknamed the Black Lord, tried to conquer three kingdoms, and he almost succeeded. But the kings united and repulsed the bloody tyrant. He was imprisoned in the Endless Tower, which stands at the very edge of the world. For many centuries, alchemists placed seals on the tower, keeping the dragon inside. But as centuries passed, the kingdoms began to fight each other again. In the fire and blood of wars, the Endless Tower and the villain lurking in it were forgotten. The seals weakened, and the usurper of the three kingdoms awoke from a thousand-year sleep...