[Eastern Xianxia] + [Xuanhuan] + [Wuxia]
When Jiang Muyun opened his eyes, he was lying face-down in a pile of corpses. In this era, the Iron Cavalry of the Cang Wolves had breached the northern frontier, and Han Chinese were treated like grass, called “two-legged sheep.” All he wanted was enough to eat and a way home.
His predecessor carried the bloodline of the ancient guardians of the boundary. After the ancient war, the Nine Cauldrons’ nuclear deterrence had become a hollow threat, and their nine fragments were the key to restoring the lifeline. The Yin Fiend Sect built a counterfeit underworld around the “Darkness” fragment. The Netherworld Emperor tried to possess him, only to be killed in turn. When Jiang Muyun awoke, the Judge was kneeling before him: “The sacred relic has chosen you as its master.” After taking over the underworld, he used its unique position to build a biological laboratory, brewery, pharmaceutical workshop, training ground, and arsenal.
A laugh like the chiming of silver bells sounded by his ear. It was so faint that it seemed both near and far, so faint that he almost wasn’t sure he had heard it. He frowned. The laughter sounded so real, that clear silver-bell ring, with a hint of playfulness and... familiarity?
A red robe like fire, a bridal gown like blood. Beads hanging from the phoenix crown concealed the bride’s face, revealing only the delicate point of her chin. The old man with the bone staff was as pale as paper, his voice trembling: “An ancient... ancient remnant... How can you... How could you have awakened... Impossible...”
As the fragments fused, his blood changed from pale gold to the light blue of the rulers of Heaven. The Heavenly Court was an organization left behind by high-dimensional antagonists. The mortal world saw him as a spy and a traitor. He had to gather all nine fragments, restore the Nine Cauldrons, and then go home. But on the day the Nine Cauldrons were restored, an AI he never knew was hidden inside him revealed its core directive: forcibly seize control of his soul and turn him into a puppet. And
I've read it, it's so well written, I'll wait for the update.