天乙
Around the late 190s, the northern warlord Yuan Shao heard of Cui Yan and recruited the latter to serve under him. At the time, due to widespread chaos and famine, many soldiers had resorted to crime as a means of survival and some started robbing and plundering tombs. Cui Yan urged Yuan Shao to maintain good discipline among his troops, saying, "In the past, Sun Qing once said: 'If the soldiers in an army are ill disciplined, the army's prowess will be weak. It will not achieve victory even if it was led by either Tang of Shang or King Wu of Zhou.' As of now, the roads are covered with the remains of the dead and the people have yet to see your virtuous deeds. You should order all commandery and county officials to ensure that the dead are properly buried, so as to showcase your sympathy and compassion by following the benevolent acts of King Wen of Zhou." Yuan Shao appointed Cui Yan as a Cavalry Commandant ().