True prince Aiden is blessed by Thor at birth but swapped by midwife Martha and raised as a slave, while her son Lucas steals his place and thunder inheritance. Enduring beatings, Aiden enters the God-Blood Duel, awakens full thunder power, defeats Lucas and sea-god heir Roland, and guards Valen's border. When the queen's seal appears, his identity is exposed. Rather than seek revenge, he holds every culprit accountable, frees the slaves, and vows justice for all.