Shattered Earth is a ruined wasteland caused by war between humans and an alien menace known only as The Swarm. Most survivors of the last war live in Old New York, a landscape of concrete and metal skeletons repurposed and rebuilt for survival. Most of the old buildings are now vertical farms and factories used to support the war effort. Every citizen has a number, rank and job assigned to them when they hit age 16. Most are drafted in to the Republic Armies and sent to the front lines to battle The Swarm.
Before the third world war a race of alien beings known only as greys came to earth to give warning and prepare the human race for the coming conflict. The alien Swarm was a product of grey experimentation with human and grey DNA that got out of hand. With their home world overrun their only alternative was to seek refuge on earth. In exchange for alien technology and know-how the greys were given refuge. But even this could not prepare us for the coming tide of war.
The swarm consisted of telepathically linked hybrid creatures, this link worked as a sort of hive mind, giving them a limitless potential for psionic power and higher thinking. The first wave of soldiers were humanoids with elongated features like greys. Their defeat caused a ripple of adaptation. Each subsequent attack was launched with a more efficient killing machine as the swarm began to learn our ways and adapt to our technology. In the current year the war has come to a halt unexpectedly. The last swarm attack was over ten years ago and the humans in Old New York sit in tense preparation for the teltale sight of alien craft on their early warning sensors.
Remenants of the Swarm’s influence live in the wastelands outside of Old New York. Pockets of bioengineered creatures live like scavengers and cannibals, testing the perimeter defenses of the outer wall.
This recursion was seeded by a fictional leakage of a strategy video game programmed in the mid 80s. The cult following that it has recieved over the years has served only to strengthen and expand it. Subsequent expansion packs and new releases have expanded the lore of Shattered Earth over the years.