In the beginning, there were no monsters, or humans and only the gods and those now known as evil gods. During those times, the world was many times larger, and flooded with a special energy called mana.
The same energy from novels and anime which allowed the gods to use magic. Magic allowed the gods to create, destroy and grow in power.
However, each god carried a unique form of mana coursing through their veins, fused with their bloodlines. In the Far East, in the cold, snowy mountains. A black wolf said to have devoured all other gods of the same race is first to be judged by others as an evil god.
Meanwhile, in eastern Europa, some gods ruled over blood or the stars. However, one particular god became obsessed with the concept of death. He created an army of undead monsters, which spread death and destruction throughout his world. This was his form of entertainment.