What do you mean, burn down the camp?

Burning camp means that the camp is destroyed by fire, which describes the defeat as a mountain.

In the first year of Zhangwu in Shu Han Dynasty (22 1), Liu Bei led an army to attack Wu in order to avenge Jingzhou and Guan Yu. Xun avoided its front, persisted in not fighting, and the two sides fell into confrontation. The expedition of the Shu army is difficult to supply, and it is impossible to make a quick decision. Coupled with the hot weather after the summer, the spirit gradually lost and morale was low. In order to relieve the heat of the sergeant, Liu Bei ordered the Shu army to camp in the mountains for the summer. Lu Xun seized the opportunity and ordered the soldiers to take a thatch with them. When they arrived at the camp of the Shu army, they set fire to it and launched a storm. The wooden fence and surrounding trees in the camp of Shu army are flammable, and the fire spread rapidly in each camp. The Shu army was in chaos, and Wu Jun even broke more than forty battalions. The success of Lu Xun's fire company camp decided that Shu defeated Wu Sheng in the battle of Yiling (the battle of Xiaoting).