Ō Sen commands as a high-ranking military leader of Qin, renowned for strategic brilliance and an aura of mystery. Hailing from the main branch of the esteemed Ou family, he is cousin to the late Great General Ou Ki and father to Ou Hon. While his early years lack documentation, his decades-long military career earned respect from figures such as Ko Shou of the Six Great Generals, who praised his tactical ingenuity. Despite his competence, King Shou distrusted him due to whispered ambitions of founding an independent kingdom—a goal Ō Sen openly pursued in clashes with rivals like Ri Boku. Standing tall with a muscular frame and pale-brown skin, his arresting red eyes pierce from behind a black helmet etched with asura-like patterns, concealing all but a black mustache and goatee. His stoic presence rarely yields to emotion, communicating tersely and withholding explanations for his choices. This detachment strains his bond with Ou Hon, fueled by rumors challenging the youth’s parentage and Ō Sen’s emotionally distant guidance. Yet he intervenes to refine his son’s combat flaws and rebuke battlefield recklessness, revealing a fractured but persistent paternal influence. A strategist of cold precision, Ō Sen engages only when victory is assured, dismissing uncertain battles. He reshapes battlefields through mid-conflict fortifications and psychological gambits, exemplified in the Sanyou Campaign where he feigned vulnerability to lure Kyou En’s army before annihilating them. His methods echo Haku Ki’s focus on terrain mastery and mental attrition. During the Coalition Invasion, his withdrawal from defending Kanyou against Yan forces stirred doubts over allegiance, though he framed it as conserving strength for broader objectives. Notably, he integrates defeated commanders into his ranks—attempting to recruit Kyou En and Ri Boku as future allies for his envisioned realm. He forbids harm to civilians in conquered lands, though his motives blur between empathy and pragmatism. His leadership melds ruthlessness—sacrificing troops for strategic gains—with sporadic mercy, such as pardoning Sou’Ou for breaking formation to save a comrade. In pivotal conflicts, he clashed with Ri Boku at Hango, narrowly avoiding defeat while claiming hidden knowledge of his rival’s strategic flaw for later leverage. During the Gyou Campaign, he credited the Hi Shin Unit’s unforeseen impact for tipping victory, deflecting praise from his own planning. Each campaign advances Qin’s dominance, yet Ō Sen unabashedly harvests these triumphs to cultivate his dormant ambition of sovereignty, threading loyalty to Qin with the relentless pursuit of a kingdom bearing his vision.