The Fox King and Ape King were both stunned. Did these underground forces want to die? If they started a war at this time, they would not care about the troops on the front lines.
It was still fine without reinforcements. The current army could contend with the humans and even have the upper hand. They could at least hold on for a long time.
However, it would be troublesome if there were no reinforcements. Because it was a surprise attack, all the soldiers were lightly equipped and did not bring much.
They did not bring any essential supplies, including the most important food. They also did not bring the tools to set up camp and live. Without these, if they could not break through the human defense line during the first attack, they would not be able to enter the city.
If they retreated, they would not be able to set up camp, and it would be extremely dangerous for them to be exposed to the human army.