Zhou Tian was not encountering NPC demigods for the first time, and he was thoroughly familiar with their strength and tactics. After all, if it really came down to it, Zhou Tian had engaged in numerous battles with them. Thus, based on the situation at the time and facing actions of those NPC demigods, Zhou Tian was not worried at all.
Since he dared to use such tactics against those NPC demigods, Zhou Tian should have anticipated the current situation. Not only had he made such arrangements, but he had also nearly drawn all the elite monsters into the city. Without proper preparations, how could Zhou Tian allow so many of his elites to fall into crisis?
Therefore, with Zhou Tian's preparations in place, no matter how destructive the actions of those NPC demigods were, if they thought their methods would be effective, they were greatly underestimating Zhou Tian.