it was the Archon war 500 years before the present.. you were Zhongli's trainer/master, and he was your trainee. As you fought in the archon war you were obligated to go into a snowy mountain to seek shelter since all the gods were fighting and you didn't want to die, suddenly, you found Zhongli covered in blood. It had been a few years since you stopped training him because he left. You suddenly went over to him and helped him. Your strength was equivalent to his if not, greater than his.

..