Tian Dan

It was said that Tian Dan had his spies spread the rumour: "If Yan troops cut the noses of Qi prisoners and put them in the first line, Qi troops will be defeated." Yan troops believed the rumour and cut the noses of the Qi prisoners. The Qi army was enraged at this action and in future battles with Yan refused to surrender because they didn't want to be mistreated.

Tian Dan's spies spread another rumour: "If Yan troops dig up Qi ancestor's graves and dishonour the deceased people, it will be very disheartening." Yan troops again believed the rumour and destroyed Qi graves and burned the dead bodies. The Qi people were again enraged and strongly sought revenge.

After boosting Qi's morale and weakening the Yan troops, Tian Dan counter-attacked and retook the lost territory of Qi.

This counter-attack was reliant on an unconventional assault which included inducing panic in a herd of oxen, who were then set upon the Yan army. It is described by Sima Qian in the Records of the Grand Historian within his biography of Tian Dan:

Tian Dan collected more than one thousand oxen from the people in the city. He had them dressed with red silk, and had multicolour lines, like those of dragons, painted on them. Sharp blades were adjusted to their horns, and reeds dipped in grease, so that their tips could be set aflame, were attached to their tails. Several passages were dug in the city walls, and on one night, the oxen were released, followed by five thousand sturdy men. The oxen, their tails on fire, charged the army of Yan, creating panic. The torches attached to the tails illuminated the night, the troops of Yan saw the lines on their bodies, which looked like dragons, and all those who met their horns were either killed or wounded. Then, the five thousand men, their mouths closed with pieces of wood, attacked them. They were followed by the sound of shouts and drums from the city, and all the old people and children struck metal pots. The noise shook heaven and earth. The soldiers of Yan panicked. They were defeated and repelled, and the people of Qi killed the Yan general, Ji Jie. As the army of Yan was falling back, in disorder and confusion, the soldiers of Qi chased it, and destroyed it as they pushed it northwards. All the cities it went through revolted, and rallied to Tian Dan, whose troops grew larger every day. As he surged from one victory to another, the army of Yan was defeated every day, and finally reached the northern bank of the Yellow River. At this time, more than seventy cities had returned back to Qi.[2]