Ever since his return, Huo Hai had been studying the Blood Mosquito Bees whenever he had time. Raising their strength was not difficult in itself, but creating new queens was another matter entirely.
The stronger a creature was, the more troublesome reproduction became. This was especially true of these queens, which needed to absorb vast amounts of a special substance to reproduce. That substance came from the brains of Blood-Colored Worms. There was not even enough to expand the swarm, let alone do anything else. Because of the Blood-Colored Worms, Huo Hai could not even raise the Blood Mosquito Bee queen's rank.
Once her rank rose, any new Blood Mosquito Bees she produced would be in the Spirit Venerable Realm. At that point, they would still require enormous quantities of the special substance, and the overall consumption would far exceed that of creating a single Blood Mosquito Bee queen.
After returning, however, Huo Hai had only discovered that Blood-Colored Worms were very easy to rear. Increasing their numbers was much harder. By stimulating their bloodlines, he had directly raised some of the Blood-Colored Worms to the Spirit Emperor Realm.
But Huo Hai then discovered that, although these Blood-Colored Worms secreted more of the substance, their reproductive abilities had deteriorated even further. Those at the lower Spirit Emperor stage were manageable and retained some ability to reproduce. Once they reached the higher Spirit Emperor stage, however, the special substance permeated their entire bodies rather than merely their brains. As a result, worms at that stage were essentially sterile.
Unable to obtain large numbers of Blood-Colored Worms, and without much time to research them, Huo Hai could only leave the matter unresolved for those two years. During that time, he completed the entire defensive spirit formation and finished modifying the other Ferocious