Hyoga Akatsuki possesses a tall, athletic build with short white hair and dark purple eyes perpetually narrowed in a squint. He initially conceals depetrification scars around his nose and mouth beneath a black mask, though these scars eventually heal fully and remain unpainted after subsequent revivals. His distinctive attire includes bird feathers encircling his neck, tan gloves, a long black cloak, a grey warrior-skirt secured by a white sash belt, and matching knee-high boots. Originating from pre-petrification Japan, Hyoga is revived by Tsukasa Shishio using nitric acid and rises as a high-ranking commander within the Empire of Might. He shares Tsukasa's ambition to forge a new world but enforces a stricter social Darwinist doctrine, viewing the petrification event as a chance to purge the "unworthy" and establish a society where only the strong, intelligent, or skilled thrive without supporting the weak. Calm and analytically precise, Hyoga rapidly dissects opponents' capabilities in combat. He exhibits ruthless cruelty toward those he deems incompetent, treating subordinates as expendable assets—demonstrated when he sacrifices his own men to test environmental hazards without hesitation. Conversely, he respects disciplined competence, trusting his lieutenant Homura Momiji with critical missions like burning Ishigami Village and acknowledging adversaries such as Kinro and Kohaku for their martial prowess. His combat identity revolves around a specialized kudayari spear, essential for executing the Kan-style spear technique. This method relies on a hollow tube allowing the spear to twist during thrusts, generating unpredictable circular motions. Without this weapon, his effectiveness plummets; his pride is intrinsically tied to this generational fighting style. Hyoga initially collaborates with Tsukasa while secretly plotting his overthrow. During the Stone Wars, he betrays Tsukasa by stabbing him when Tsukasa shields his revived sister Mirai. Hyoga then attempts to forcibly recruit Senku Ishigami, valuing his scientific genius but threatening torture to ensure compliance. Senku and Tsukasa temporarily unite to defeat Hyoga via electrocution, resulting in his imprisonment. Later, during the Treasure Island conflict, Senku revives Hyoga as a last resort against Mozu and Ibara. Hyoga allies with the Kingdom of Science after deducing Mozu's untrustworthiness and shallow principles. Wielding an upgraded kudayari spear modified by Senku, he defeats Mozu while asserting that rigorous training can surpass innate talent. Both are petrified shortly afterward. In the voyage to America, Tsukasa requests Hyoga's revival to train the Kingdom of Science in weaponry. Hyoga agrees on condition that Homura and Mozu are also revived—honoring a promise to spar with Mozu. Despite residual friction with Tsukasa, they cooperate practically during tasks like hunting alligators for supplies. Hyoga remains tactically observant, identifying traps set by Stanley Snyder's unit and employing improvised armor to reduce injuries. Hyoga's ideology evolves subtly: while initially advocating killing the weak, he later accepts leaving them petrified. He retains his elitist worldview but pragmatically aligns with the Kingdom of Science for resources and worthy adversaries. His relationships shift from hostility to conditional alliances with former rivals like Tsukasa and Mozu, though interactions with Senku stay strictly transactional.