Long ago, an insidious black beast sought to obliterate the human race, but the monster was defeated by a valiant Band of Heroes wielding the power of Ars Magus: a potent combo of magic and technology. Now, a roguish outlaw known as Ragna the Bloodedge seeks to wreak havoc upon the Librarium, a clandestine organization that governs Ars Magus. Armed with the mighty Azure Grimoire, Ragna quickly becomes the target of vigilantes, scientists, vampires, and Librarium foot soldiers. As he spirals toward a violent showdown with the maniacal Hazama, Ragna will discover just how closely his fate is tied to the future of our world!