Cross the border
It is still the moon and border pass in Qin and Han dynasties, and the enemy has fought a protracted war. But make Longcheng fly, and don't teach Huma to cross the Yinshan Mountain.
Join the army and do the fourth thing.
There is a dark snow-capped mountain in Qinghai, with long white clouds and a lonely city looking at Yumenguan. Yellow sand wears golden armor in hundreds of battles, but the loulan is not returned.