The most important point is that aside from his vast territory, Zhou Tian surprisingly has three Pope-level mini-bosses under his control. Given the great power Zhou Tian has continuously demonstrated, many of the bosses had no choice but to admit that Zhou Tian now has the qualifications to compete with the Corpse Demon and those Elemental Spirits.
Even monsters who truly understood Zhou Tian could confidently assert that Zhou Tian's strength had surpasses that of the Corpse Demon, making him the second most powerful monster force at this time.
The Corpse Demon's strength was only due to possessing a powerful boss. But if the real strength was compared, Zhou Tian wouldn't be weaker than his opponent at this time. Given this, if the three Pope-level Giant Bears under Zhou Tian's command were also counted, then even if the territory of the Corpse Demon's clan was not smaller than Zhou Tian's, they absolutely wouldn't be able to defeat Zhou Tian.