Because of Xiaotian, most of the history of this world had changed.
For instance, since Jingzhou belonged to Xiaotian, Wan Cheng naturally belonged to him as well, meaning Cao Cao had no need to attack it, as they were all on the same side.
Then there were Zhang Xiu and Zhang Ji. Both of these men were still alive. In a previous version of events, they had wanted to attack Jingzhou, but Zhang Bao was no pushover.
Chapter 149