AD 1279, Yashan.
One hundred thousand soldiers and civilians of the Southern Song Dynasty were besieged by the Mongolian army, and the death knell of Lu Xiufu carrying the little emperor across the sea was about to ring.
Lin Jiu, the chief engineer of a modern military industrial enterprise, traveled through time and space in an experimental accident and became an unknown primary school student under Wen Tianxiang.
He does not have thousands of troops or unparalleled martial arts. He only has an "Alien Library" system that was accidentally activated - which stores all the scientific and technological documents since the Industrial Revolution.
When everyone thought that the Southern Song Dynasty would be destroyed, Lin Jiu saw the only possibility of a comeback:
Use technology to reduce dimensionality.
He started with the most primitive metallurgical improvement, selling gunpowder formulas on the black market in exchange for the first pot of gold; he designed the first iron cannon that did not explode, and established a secret arsenal on the rocks of the cliff mountain;
He trained the first musketeer battalion and used the three-stage strike tactic to tear apart the Mongolian cavalry charge.
But technology cannot change people's hearts.
Wen Tianxiang regarded him as a monster, and Lu Xiufu called him a deviant. Even the soldiers he trained doubted whether this "firearms monster" would lead the Song Dynasty into a deeper abyss.
What's even more frightening is that the Mongols are not fools. When they realize the threat of hot weapons, the cavalry in the entire grassland will turn their spearheads and target this small arsenal.
Lin Jiu has only one choice:
Before the Mongol Khan could react, he used steel and gunpowder to create a brand new Song Empire.
Either industrial revolution or national subjugation and genocide.
