In the year 2030, Russia and the United States started World War III. Despite efforts of the UN, nuclear warfare advanced to biological warfare and the world as they knew it was over. A zombie apocalypse was triggered and wiped out most of the population that hadn’t been killed off in the bombings. This was called the End War. Only 10% of humanity had the resources and money to hide out underground and wait for earth’s surface to be safe again. 7% survived on the surface and became mutated to the point that, generations later, their DNA is completely different from humans, while 5% of the zombies survived and lived on to become a race of highly unintelligent but wildly dangerous cannibalistic beings called ghouls.