Boiling and Howling

The Blood Sea.

This is one of the Ten Seas in the world. Mystical, deadly mysterious. 

This is the most common attributes that all the Ten Seas shares with each other.

In the Blood Sea, there is many terrifying creatures. 

From the fishes, to the monsters, all of them have this ghastly quality to them

There's also zombie-like creatures. Their flesh is rotten and sometimes they could be seen on the rocks near the Blood Sea shores.

Unlike the mutated homo sapiens, these zombie-like creatures did not attack people unless they are provoked. And when they are killed, they turned into a mist of blood. 

And this mist of blood would return to the Blood Sea. 

Hence there is a theory proposed by the Order of Thinkers that the Blood Sea is alive. 

And all of the creatures in the Blood Sea are creatures that are created from the droplet of water in the Blood Sea

These zombies, these terrifying fishes is only the small fry.