Great Qin: The Heavenly Dao Gold Rankings Reveal Ying Changsheng

Ying Changsheng transmigrates into the body of Qin's nineteenth prince. He devotes himself to keeping a low profile in an underground city, where he builds a sci-fi Heavenly Court and develops planet-destroying cannons and water-drop weapons. But then the Heavenly Dao descends and announces a ranking of divine weapons, and his era-defying "toys" seem to be on the verge of being exposed.