The North Sea Water Demons led by Great Sage of Sea Quelling and the other two had already been exposed during their last battle with Demon Emperor Seventh Crown Prince Cong Yun.
Ye Zhen feared that once Demon Emperor Second Crown Prince Zhui Ri arrived, the first thing he might do would be to purge the North Sea Water Demons from the Blood River and eliminate this hidden danger.
Though twenty thousand elite North Sea Water Demons were not many, at a critical moment, they could change the outcome of a battle.
For this reason, Ye Zhen had prepared for a rainy day and instructed Great Sage of Sea Quelling and the other two to find suitable hiding places in the Blood River as early as possible.
They were to build underwater camps in advance as a precaution, prepare escape channels early, and secure more places to hide.
Thus, over these past days, Great Sage of Sea Quelling and the other two had led the North Sea Water Demons in thoroughly exploring the Blood River, seeking hiding places and preparing underwater escape routes.
After all, the world beneath the water was disconnected from the land. So long as they made proper preparations, the North Sea Water Demons would not fear even an encirclement by a great army.
Things had been normal at first. They had found several concealed hiding places and prepared several secret escape channels.
But just yesterday, a water demon had accidentally rushed into an inconspicuous whirlpool on the riverbed and discovered another world.
Yet this new world beneath the Blood River whirlpool was incomparably strange and concealed all manner of secrets.
After Great Sage of Sea Quelling and the other two studied it for nearly a day, the more they studied it, the more alarmed they became.