If Zhou Tian did not enter the opponent's castle, it meant that he could never capture it. In that case, there was no difference whether Zhou Tian attacked those NPC cities or not. If Zhou Tian did not enter the opponent's castle in such a situation, it would have been better if he didn't bother attacking those NPC cities from the start.
Although the territories occupied by those NPC cities were small, the locations of all the cities built by the NPCs were at crucial points. If Zhou Tian turn a blind eye to their existence, Zhou Tian would be out of luck someday if those NPCs were to take action.
Hence, just based on the positions occupied by those NPCs, Zhou Tian absolutely could not leave them alone.
In this environment, where neither attacking nor not attacking the opponent would work, Zhou Tian didn't really have any good ideas about the war at that time.
