One - God of Doom

Almost two centuries ago, the god of doom appeared and humanity lost almost hundred percent of its population. Only a few hundred survived his arrival.

Humanity would have to start from scratch. Unfortunately, the god of doom hasn't even attacked yet.

Every twenty years, humanity sends its elite ten warriors to fight the god of doom in his temple. It is said that if humanity fails to defeat the god of doom a tenth time, all humanity shall perish.