Kolliderte

Kolliderte is the name for the world that was born after the world-ending collision of several planes of existence. The cause of the event is currently unknown.

Those who survived the tragedy were misplaced onto not a whole planet, but a series of floating archipelagos made of mismatched pieces of realms. It was akin to making a jigsaw puzzle with pieces from different boxes, a desert next to a tropical jungle, a floating kingdom in the sky overlooking a modern city. Some inhabitants managed to stay with the land they had lived on, but many were misplaced into a biome or culture they were very unfamiliar with.

With the many planes came many races, some humanoid, some not, some of demonic origins, others of celestial. Despite their differences many were forced to work together to survive on the islands in Kolliderte, struggling to maintain life with limited land and resources. 

There also came monsters. None knew what plane they were from, creatures of shadow that held no sentience and attacked the stranded survivors in the night. They soon discovered the monsters bite was infectious, staining the skin with black ichor that consumed the wounded from the inside out like poison and turned them into a faceless shadow like the others.