Background....

The 21st Century looked as if it was going to be a golden era. Wars were at an all time low, nuclear arsenals were cut down to a fraction of what they once were and the environmental disasters feared by the 20th Century never materialised, through a combination of nano-technology to clean up the existing problems and then shifting heavy industry to space.

But then in 2079 it all went wrong.

Warheads rained down from space and within the space of a week a quarter of the worlds population was exterminated as cities became glowing radioactive furnaces.

They were the lucky ones.

Wave upon wave of mutagenic viruses struck at human and animal alike, and high tech nano wepons ate at the computer circuits, electricity cables and plastics that civilasations depended on. As the infrastructure collapsed, billions starved.

Nowhere on earth was spared these deprevations, and it soon looked as if the only pockets of humanity that survived would be the ones hidden safe within bunkers, deep underground.

But not quite.

In the years between 2080 and 2140 life was viciously hard for the few survivors that remained on the surface. Horribly altered by the effects of both the viruses and the radiation they struggled to eke out an existence constantly under threat by the voracious fauna and flora of the new world. But after two generations the weak had died out and only the strong survived.

Groups banded together for strength and protection, building wepons out of whatever they could find, and began to tame many of the animals and plants they came across. A civilisation based on strong warrior ethic had begun to emerge. Scavenging what they can from the old times, they rely on their animals more than technology.

Meanwhile...

Down in the shelters, original estimates of how long their supplies would last are proving hopelessly optimistic. Recycled food supplies were still adequate, if not enjoyable, but their technical resources were being stretched to the limit. Eventually it became obvious to the shelter dwellers that they would have to return to the surface before they were completely denuded of technology.

Under the control of the council of the Council for survival, the shelter dwellers started up their tunnelling machines and begun drilling back up to the surface.

They broke through in 2141, thirty nine years sooner than their original plan called for.....