A few years later.
The past few years Ying Zheng had an easy time. He conquered all the remaining states and turned their resources be it financial or human into a working a perpetual motion resource machine that just keeps powering itself from the conquests.
Ying Zheng had even introduced even introduced the banking system of paper money.
Ying Zheng respects and even looks up to human beings. They can turn useless paper into a god.
The use of paper money was not very popular at the beginning but as time went on people just kept using the paper money in return for goods and resources. Seeing the mighty Qin dynasty backing up the money people forgot about gold and silver in months and in return Ying Zheng kept on creating smaller and smaller money for them to use in exchange for resources.
What Ying Zheng loved about paper money was that he could use non-existent money to fuel his never ending wars. He just had to stop inflation or lack of money.