The weather in Chenping, Nanning
Although the Huns are brave, they are nomadic. In fact, they invaded the southern man for money. Liu Bang was trapped in Deng Bai. In order to get out of trouble, he will naturally pay a lot of money. The purpose of modu chanyu has been achieved, without catching Liu Bang or killing Liu Bang. Although it may be more advantageous to capture Liu Bang alive, the weather did come in a severe winter, and Liu Bang's reinforcements did not know when they would arrive. For modu chanyu, that's for him.
Although E Shi was afraid that the beauty sent by the big fellow would take her place, she would persuade Mo Duhan, but she also pointed out the crisis of Mo Duhan at this time. Huns just want to make money, and the goal can be achieved. And fighting didn't yield much, and it is possible to lose more, so the magic capital Khan will listen to E Shi.
In fact, the situation at that time seemed dangerous, but Liu Bang was not lifeless. Even if Morton wiped out 10,000 Han troops, Liu Bang was likely to break through. Once Liu Bang breaks through, Morton will be in danger, so Morton will let Liu Bang go.