Da Qin: the Tavern Owner Is Actually the Eldest Grandson of the First Emperor

The modern time traveler transformed into a Xianyang tavern owner and drifted by the Hengshui River with a wooden basin when he was young. Ying Zheng and Wang Jian came to investigate and found out the identity of the missing grandson based on the word "Ying" on his clothes. Their request for a large sum of money to buy tokens was rejected. The protagonist is sure of the gold and sees through the plots of all parties in the court.