Earth, 500 years from now, has endured the Fifth World War. This war employed a biological weapon more terrifying than nuclear arms, known as Ling. As a result, only 10% of humanity remains, fewer than a billion people. The habitable land on Earth has shrunk to just one percent of its former size, and most settlements have been built out at sea. After exposure to radiation from the biological weapon Ling, the plants and animals on Earth underwent genetic mutations. Dead animals became zombie monsters, while the living became intelligent monsters. Whatever they were, they devoured everything edible around them, including their own kind, metal, and building materials! Of course, their favorite food was people. To ensure the continuation of the human race, people from every nation joined forces to fight the threat to humanity and formed a massive international organization called the International Defense Alliance, or the National Treasure Alliance for short! This year is also known as the first year of the Historical Era.
