Chu Mu only knew after going underwater that the coral island above water was just a tiny portion of the entire structure. This coral island became an enormous structure once he saw the portion underwater.

There were countless coral caves that could be crossed through. They were big and small, complicatedly connected with one another. It was like a maze after swimming into it.

The water around here had special dark currents. They could be carried somewhere without really swimming. Of course, these dark currents were gentle. They seemed to be traffic guidance and accelerated the speed of oceanic creatures, as well as helping the oceanic creatures determine their direction.

The underwater coral island was divided into many layers. After the mermaid led Chu Mu and Ning Maner to pass through various Ocean Species habitat, they reached the bottom part of this entire underwater city, or perhaps it could be said to be the city center.

Various oceanic creatures swam past Chu Mu. They looked at Chu Mu and Ning Maner curiously and confusedly.

In a...