Now Zhou Tian realized why the undead had chosen to fight to the death rather than abandon their territory. It turned out that the undead were already aware of the situation outside. They knew that if they let go of their domain, they would have no chance of victory against the external monsters. So, they decided to persist.
Zhou Tian had not anticipated that the situation outside would evolve to such a point, and that's why he had been helping the organization dismantle their undead domain. Yet, now that they've actually removed the Undead Domain, Zhou Tian felt somewhat uneasy. After all, given his identity, the undead were hostile to him, and the organization might not necessarily feel positively about him either. As Zhou Tian is now within their sphere of influence, nobody can guarantee that the organization would let him off the hook.