I'm Swinging a Sledgehammer at the Great Wall

The center of the King's Continent is the most powerful country - Tang. To the northwest of the Tang Dynasty was the Great Wall. What was the purpose of building the Great Wall? What is the purpose of guarding the Great Wall? Different people gathered at the Great Wall with different destinies and different purposes. In front of them was the vast desert and the ambitions of demons. Behind them were the lights of thousands of families guarding them, but they still had to worry about the cold arrows shot from behind. I wield a sledgehammer on the Great Wall and build a high wall called responsibility. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.