Farming, reclaiming wasteland, and building a city; an overhead view of the planning; no modern firearms; no marrying a princess; Li Er only appears later in the story.
The good news: he got a System that lets him travel between the modern era and the Tang Dynasty.
The bad news: in three years, he’ll be stuck in the Tang Dynasty for good.
To protect himself, Kui Yang starts stockpiling supplies, establishing a village, growing high-yield crops, and building a militia.
He only meant to protect himself, so how did he end up building a city?
Militia captain: “Just say the word, Lord of the City. I’ll take eight hundred brothers and go head-to-head with Li Er at Xuanwu Gate.”