On My First Day in Ancient Times, I Pulled Out a Shotgun

Shen Xingchen accidentally transmigrates to ancient times, to the Kingdom of Wuzhou, where the people suffer as the country is torn apart by war at home and abroad.

Just then, Shen Xingchen discovers that he can travel freely between the modern and ancient worlds. He grabs some grenades, shoulders an AA-12 automatic shotgun, and sets off.

From then on, a figure feared by the enemy appears across the land of Wuzhou.