I would suggest posting this again if not already done
If there’s an option about opposite angles, then I would say that’s it
During this era, human technology boomed. In this era, nomads have started farming. Nomads have stopped moving from one place to another. They have started forging metal tools. They also started pastoralism. They have communities and tribe. They were able to create a system on their own.
Plague is a deadly disease that people are afraid of.
