The strength of the monsters who came to take advantage of Zhou Tian this time was in itself not remarkable. Anyone would know that even Zhou Tian has the power to take down this undead territory in one fell swoop. If this undead territory were to border the territory of some advanced monsters, it would have probably been swallowed up by them already.
Since Zhou Tian annexed that territory, this also explains that the only opponents Zhou Tian needs to face now are a bunch of middle-level monsters with mediocre strength. Not to say that they pose no threat to Zhou Tian, but apart from their numerical advantage, it's expected that none of the handful of monsters can surpass the strength of the Beastman Tribe.
