Seven Knights Revolution: Eiyuu no Keishousha

In the past, Heroes defended the world from forces of Destruction. Over time, they vanished, leaving behind individuals known as Successors who inherit their abilities. In the present, one of the Seven Knights, a group of elite Successors, confronts an army of Destruction and rescues a boy named Nemo. During the conflict, Nemo unknowingly activates Heroic powers, revealing himself as a Successor. His Hero, however, is an unknown figure with no recorded history.