Great Tang: I Snatched Princess Changle from the Start

A young man from modern times transmigrates to the Tang Dynasty and becomes the only son of the Duke Who Guards the Nation! And his father-in-law is Li Shimin? He awakens the War God System, only to discover that the seven-year-old Princess Changle is to be married off to the Turkic Khagan! Armed with a military order, the princess's consort leads an army of 300,000 to intercept the wedding procession and rescue her! A dark-gold Cloudpiercer Spear stands atop the city wall, and the enemy army immediately retreats a hundred li! Li Shimin says, “My worthy son-in-law, I am ashamed by comparison. You should take the throne in my place!” The Turkic barbarians cry, “As long as the Tang Dynasty's God of War lives, we will submit without conditions!”