In the ancient era the ancient God's created so many world and given spiritual energy to the people to protect themselves from shadow of evil.
There are 10 great world --- The god realm, heaven realm, Mortal realm, Spirit realm, Demon realm, Shadow realm, Beast realm, Dragon realm, Star realm and the Chaos realm.
In those world there is only spritual energy that helps to become stronger and to attain immortality.
These people cultivate this energy to become young and strong to rule the weak. They don't care what happens to the mortal because they want powers.
The spiritual power was divided into 12 stage. They have to reach these stages to attain immortality.
Those stages are:- Mortal, Warrior, Master, Grandmaster, Spirit, King, Emperor, Ancestor, Venerate, Saint and The God
level.