"War God" O'Brien is the founding emperor of the O'Brien Empire.
He has a head full of long, scarlet red hair, and his gaze flashed with dagger-like light.
He has a very calm and calculating personality. This extends even to the point that years prior to the Necropolis of the Gods' opening, he arranged the marriage between Wharton and Nina in order to give Bebe face.
Five thousand years ago, during the great war between deities in the Yulan Plane, after reaching the limits of Saint level, O'Brien was fortunate enough to acquire the divine spark of a Demigod. He then absorbed and fused with that divine spark… and thus, O'Brien became a Deity.
The War God O'Brien founded the O'Brien Empire sometime later. He is also the highest authority in the O'Brien Empire, transcending the power of the ruling emperors with ease. During his and Linley's first meetings, he was seen training inside one of the peaks of the Wargod Mountain, engulfing himself in a glowing ball of lava.
He tells Linley about the Necropolis of the Gods and subsequently invites him to join in the exploration when the time arrived.
He met Linley and his group again atMiluo Island, inside of the Starmist Sea. He, by that time, had already managed to attain the rank of Highgod by the means of fusing with a Highgod Spark gifted to him by Tarosse.