Liu Zhaoji laughed and said, "Master Yan, have you read too many novels?"

"What do you mean?" Yan Yingyuan stood up with his eyes wide open. "The Mongols can fight to support the war, so why can't we?"

"It's possible, but it's difficult!" Liu Zhaoji sighed as he spoke: "Take the cavalry as an example. The upper limit is to carry seven days of rations."

"According to the marching speed of 100 miles per day, we must return after 300 miles, otherwise we will run out of food."

"Right?" Liu Zhaoji stopped at this point.

"Yes, yes," Yan Yingyuan nodded in agreement.

"Okay, now here comes the question!" Liu Zhaoji's expression began to become serious: "When we travel 300 miles, we happen to encounter a tribe. Should we fight or not?"

"Of course we will!" Yan Yingyuan said immediately, "The purpose of our expedition to the grassland is to fight the Mongols!"

Liu Zhaoji's face became more serious. He frowned and said, "It would be fine if we win. The tribe's population and money and food will all be taken into our pockets. But what if... we lose? No one can guarantee that they will win every battle, right?"

Unbeatable...?

Without waiting for Yan Yingyuan to think about this question, Liu Zhaoji continued: "If we lose the battle, we will not only lose soldiers and generals, but also waste a day's rations. If the enemy sends troops to harass and pursue us again, our cavalry will be chased to death and starved to death!"

"Even if we win, the nearby tribes will either flee or unite to resist after hearing the news, and then our army will face the same problem again."

"This is just a human problem. It takes a lot of time for war horses to graze and eat grass. Without a supply of grass, it is almost impossible for war horses to travel a hundred miles a day. War horses can also be fed grain, but their appetite is five or six times that of soldiers!"

"Wait..." Yan Yingyuan interrupted Liu Zhaoji: "What did the Mongols do when they marched westward?"