Let me get this straight. Zhang Xun and his forces of 60,000 people were in a battle or conflict for so long that they ran out of food, ate the horses, and the procedure to resort to cannibalism, first starting with the woman, then the old men, then the young boys, and then from there picking the weakest of the group that was left for who would get eaten next until the force was down to 400 survivors? And they considered it acceptable losses?
I imagine it was considered a strategic Tang victory even though it resulted in a loss of the city, because without the time bought by the seige, the Tang would not have been able to put down the rebellion.
The Taiping Rebellion. Basically a Chinese guy claims to be the brother of Jesus and leads a pro-Christian rebellion against the Qing government that results in more deaths than the first world war
"He ordered his troops to shoot weeds, instead of arrows, at a few enemy soldiers. When these soldiers noticed that they were being shot by weeds and left unharmed, they were overjoyed. They promptly ran to Yin Ziqi to report that the Tang army had already run out of arrows. Zhang Xun noticed where the soldiers ran and ordered his best archer, Nan Jiyun, to shoot at Yin Ziqi. One such arrow hit Yin Ziqi in his left eye, throwing the Yan army instantly into chaos. The siege ended with the expected major blow to Yan morale."
That would be amazing if it actually had happenend.