The process of building Nether City was much steadier than building Demon Suppressing City.
Huang Yu spent three days upgrading Nether City to Tier Five, yet it did not suffer a single large-scale assault from undead creatures along the way.
There had been no major battles, but there had been plenty of minor clashes.
That was also an unavoidable part of expanding the territory.
First came the Death Dirge Legion's cleanup of the wild undead in the surrounding area.
Aside from the seven Tier Six and Tier Seven undead that had initially been captured and controlled, along with the undead under their command,
all the other wild undead within fifty kilometers of Nether City had been thoroughly cleared out by the Death Dirge Legion within three days.
Those seven undead and all their subordinates had now been assigned by Huang Yu to the Death Dirge Legion, serving as their enforcers and cannon fodder.
After helping the Death Dirge Legion deal with the wild undead near Nether City yesterday, they had now been divided into four units to expand into and explore other regions.
At present, the only undead active near Nether City were those created by Huang Yu's Bone Resurrection.
To speed up the development of resources in this area, Huang Yu's undead labor force had grown to nearly ten thousand.
Aside from skeleton undead, Huang Yu had also taken control of a batch of Ghost Undead and Imp Undead.
The low-level Walking Corpse Undead were too stiff in their movements. On top of that, they carried either viruses or plagues, so Huang Yu did not favor them.
As a result, one could hardly see any of them among Nether City's labor force.
The reason Huang Yu controlled Ghost Undead and Imp Undead was that the former could move freely