Leon's sheltered life with his father, Artorias, in the monster-infested Forest of Black and White, is meticulously crafted for his bloodline's awakening. Artorias, a former noble from the Bull Kingdom, pushes Leon to hone his killing intent through hunting, culminating in a perilous pursuit of a Snow Lion. Despite Leon's third-tier strength, the hunt is a brutal, near-fatal encounter, forcing Artorias to intervene at the last moment. This harrowing experience is merely a prelude to the true trial: the bloodline awakening ritual on Storm Titan's Mountain. Drinking the Snow Lion's mana, Leon's body is ravaged from within by the beast's power and from without by the ice wraith core's lightning magic, pushing him to the brink of death. As his body shatters, the Thunderbird, his ancient ancestor, directly intervenes within his soul realm, not only healing his grievous wounds but accelerating his adaptation, catapulting him to third-tier status. This immense surge of power manifests as a terrifying storm, noticed across the continent by the most powerful mages of the Central Empires and even the distant Planar Lord, Ambrose, signaling the emergence of a new, potentially world-altering force, yet leaving Leon oblivious to the true extent of his awakening's impact.

The elation of Leon's awakening is short-lived, as an elite kill team from the Isynos family, led by Timotheos and Adrianos, invades their fort. Artorias, despite his immense power, is caught off guard and mortally wounded by a poisoned dagger while protecting Leon. In his dying moments, Artorias reveals his identity as Artorias Raime, the Archduke's second son, and the tragic loss of Leon's mother, Serana, and the Raime family palace. He charges Leon with a final task: destroy the obelisk, claim his inheritance, and seek his destiny. Following his father's instructions, Leon buries Artorias's body with a heartwood seed, an ancient ritual guided by the Thunderbird within his soul realm, which further strengthens his bones. Driven by grief and a burgeoning desire for revenge, Leon burns their home and ventures into a hidden prison system beneath the Frozen Mountains. There, he encounters Xaphan, a powerful but imprisoned fire demon. Through a tense negotiation, Leon leverages Xaphan's desperation for freedom into a binding contract, exchanging release for knowledge, power, and partnership, unknowingly gaining a powerful, albeit sarcastic, ally.

Leon emerges from the demon prison, now a third-tier mage with a dual affinity for lightning and fire, and a demon partner residing in his soul realm. He journeys to Teira, the former seat of House Raime, seeking information and resources. There, he encounters Charles, a talkative commoner he inadvertently saves, who becomes his guide. His visit to the Heaven's Eye Bank reveals his family's immense wealth and, more critically, the name of Adrianos Isynos, a man-at-arms Roland had sought, confirming a direct link between the attackers of his home and the Bull Kingdom. This encounter also introduces him to Elise, a captivating Heaven's Eye manager who develops a keen interest in him. Deciding against immediate confrontation, Leon embraces his father's lessons of strategic caution and chooses to enroll in the Knight Academy in the capital. He trains Charles, transforming his shaky first-tier foundation, while preparing himself for the rigorous entrance tests, determined to gain the power and influence needed to avenge his family and uncover the full truth behind the Raime dynasty's downfall.