...East-Blue, West-Blue, South-Blue, and North-Blue are the four seas that constitute most of the whole planet. Humanity is thriving on the small patches of land which poke out of the four seas. These four seas are separated horizontally by a humongous mountain which encircles the whole planet, called Red Line, and vertically by, the most dangerous sea known to man, Grand-Line. Both sides of Grand-Line are flanked by strips of the windless sea called Calm Belt. The eternally windless strips of sea are impossible to cross with only wind-powered ships. It might be calm over the water, but the water hides nasty beings called sea kings, not to be disturbed as the name suggests.

People in this world can train themselves past any and all physical limits, only their mentality is the problem. A strong mind makes the body strong. Everyone in this world possesses this almost magical power in them called haki. There are three types of haki, two available to everyone and the last one is seen only once in seven million people. Different haki can be used to strengthen the body to even affect logia users, to predict and to foresee attacks, sense others' prowess and even exert your will upon others.

Fruits of the sea devil. Otherwise know as devil fruits, give miraculous powers to those who eat them, but robs them of their power to swim and makes them vulnerable to anything from normal seawater to the crystallized power of the sea, sea stone. Devil fruit powers are categorized into three different categories: Zoan type fruits allow their users to transform into an animal of a sort and gain their abilities. There are also human and mythical type zoans so they should actually be called transformation powers but those ones are extremely rare to the point of none existent that most just associate zoan transformations into animals. Logia fruits make their eaters become the element that the fruit was. For example, the one who eats the fire logia fruit is able to use fire in their attacks, become fire to avoid physical attacks and much else. Last but not least are the Paramecia fruits, these fruits are undoubtedly the weirdest and most random of the bunch. There are some that let you attract metal, make you slim and slippery, make your body able to split your body into many pieces, makes your body rubber, lets you control vibrations, light, pressure almost anything you can imagine.

Lastly, there are two opposing factions in this world. The marines and the pirates, most strong people are part of either one. Both have their ups and downs. Pirates are free people who do whatever they want. Good or Bad. Marines are the upholders of justice in this world yet no justice system is without corruption.

I closed the introductory book while frowning.

"Isn't this a summary to the one piece world...?"