In the devastating world war of the 23rd century, tens of thousands of nuclear bombs dropped by various countries regardless of the cost, turned all seven continents into scorched earth, swallowed by the waves, and submerged by the ocean. The civilization of the continent was drowned by humans in the blue abyss and turned into the new Atlantis. There was only a lonely island chain left in the vast world, continuing the last spark of human civilization.
On the last human settlement known as the Polikova Islands, two forces are competing against each other - Yutang, the original Asian ethnic group on the island, and the Solelet Association, an alliance of exiled survivors around the world. The two sides have been competing for more than half a century. Their scientific and technological civilization has far surpassed that before the war. They have stored post-war nuclear radiation and biological and chemical pollution in the polar seabed, and want to use the archipelago as the core to reconstruct a new continental civilization. There is a bay full of deep water whirlpools in the sea on the west side of the archipelago. According to legend, there lives in it a creature with the body of a dragon, with red scales like blood and a long tail like a blade. This sea area, which is feared by humans on the island and has been classified as a restricted area, is named the Sea of Blood. This mysterious and unknown race is called the Blood Scale.