Chouetsu Kyuu Seikenshi, Makenshika no Sue Musuko ni Kaiki suru

Humanity stands on the precipice of annihilation, overwhelmed by a relentless alien threat known as the Invaders. Zenon Glorious, an elite Nine-Star Holy Swordsman, wages a desperate final battle against them. Through the ultimate sacrifice of his fallen comrades, he is granted a miraculous second chance and hurled back through time to alter history’s tragic course. When Zenon awakens, he discovers he no longer inhabits his own body. Instead, he has been reborn as Noah, the youngest son of the esteemed Daskul family—a boy universally scorned as a worthless failure. Yet beneath this despised exterior lies the hardened soul and tactical brilliance of a legendary warrior who has already witnessed the end of the world. Determined to prevent the catastrophic future he once endured, Noah leverages his retained knowledge from his previous life to forge an unprecedented path. He wields a singular, forbidden ability: the Magic-Holy Core. This impossible fusion merges a magic core and a holy core—two fundamentally incompatible forces that were never meant to coexist. Armed with this extraordinary power and the memories of a dying world, the disgraced youngest son rises to confront the Invaders and rewrite humanity's fate.