Long ago, the Earth was ruled by enormous lifeforms known as Horn Beasts. Possessing overwhelming power, they mysteriously vanished from the world after being sealed away within objects called Egolgia. In the present day, people have learned to draw upon the power of the sealed Horn Beasts using devices known as Kakuseiki. These individuals become known as Hunters
One day, Shout discovers an ancient Kakuseiki and an Egolgia resting on the altar of an ancient ruin. Although the device, called the Omega Horn, differs from the Kakuseiki used by modern Hunters, he decides to activate it by inserting the Egolgia. In response, a gigantic horned beast named Enkaku appears. Recognizing in Shout the unwavering spirit and determination that embody the qualities of a king, Enkaku asks him to take up the title of Captain Omega Horn and fight alongside him.
As numerous Egolgia and the Horn Beasts sealed within them begin to emerge, Hunters battle one another to obtain their opponents’ Egolgia, whether to fulfill their dreams, seize power, or pursue their own ambitions. Together with Enkaku, Shout enters these fierce Hunter Battles, gradually strengthening both his resolve and his own sense of self.
