Yan Yun Zhi: the Fire of Saltpeter Illuminates Yan Yun, and the Iron Horse Fixes the Mountains and Rivers.

The time traveler Zhao Yi woke up on the battlefield of the Northern Expedition in the third year of Yongxi reign of the Northern Song Dynasty (986). Faced with the inevitable defeat of the Song army, he founded the Gewuyuan with modern knowledge, promoted gunpowder upgrades, water transportation reforms and military innovations, triggering a chain reaction: helping the Song army achieve a tragic victory at Qigou Pass, promoting the early conclusion of the Chanyuan Alliance, and finally regaining Youzhou. But technological leaps have hidden dangers - Empress Dowager Xiao of the Liao Dynasty vowed on her deathbed to eradicate "the art of studying things". The "Fire Thieves" uprising broke out among the people due to the spread of technology, and countless ordinary people (such as Qian Sanniang, Tiezhu, etc.) Became silent victims of the change. In the past forty-four years, Zhao Yi competed across the river with Yelu Longxu, the Emperor of the Liao Dynasty, reached a political alliance with Liu E, and joined forces with Yang Yanzhao and other generals to promote change. However, he was always trapped in a technological ethics dilemma: Is progress worth the cost of ethics and humanity? The story is not only a journey of hard-core technology to rewrite history, but also an epic dedicated to the unknown - when the torrent of time swallows up individual memories, "remembering" becomes the only dignity to fight against forgetfulness.