War never changes.
The Romans waged war to gather slaves and wealth.
Spain built an empire from its lust for gold and territory.
Hitler shaped a battered Germany into an economic superpower.
But war never changes.
In the 21st century, war was still waged over the resources that could be acquired.
Only this time, the spoils of war were also its weapons.
Petroleum and uranium.
For these resources, China would invade Alaska, the US would annex Canada, and the European
Commonwealth would dissolve into quarreling, bickering nation-states, bent on controlling the
last remaining resources on Earth.
In 2077, the storm of world war had come again.
In two brief hours, most of the planet was reduced to cinders.
And from the ashes of nuclear devastation, a new civilization would struggle to arise.
A few were able to reach the relative safety of the network of fortified Vaults.
Your family was part of the group that entered Vault G.
Imprisoned safely behind the space station’s bulkheads, floating above a sea of vacuum, a
generation has lived without knowledge of the world below.
Life in the Orbital Vault is about to change."
Where underground Vaults are numbered, the orbital series is lettered. There are only a handful of Orbital Vaults. You are from Orbital Vault G, but that doesn't mean that there are necessarily seven OV's. First thing, most of the OV's were incomplete when the missiles launched, so for many of them, including OV G, the inhabitants lifted with more than half of their Vault's materials, and for those whose shipments weren't ready, they didn't lift at all. Second, the space war lasting a few days after Bomb Day was very intense, with military space stations being liberal with nuking every damn ping on the scope. Thanks to the radiation storms, Vault G has contact with only one other OV, Vault F. Since each is better equipped to handle certain aspects of spaceborne living, they have a trading partnership. Vault F, for example, has a spaceplane that can skim oxygen and nitrogen off Earth's outer atmosphere, which they trade for scrap metal from G, which has a lander that can access the only known non-irradiated salvage yard on Luna.
Vault G is in geosynchronous orbit over Denver, Colorado, and its components and occupants lifted mostly from the Boulder Astrodome in Boulder, Colorado. Its original occupants, and those of all the Orbital Vaults, were from technical backgrounds and trained for spaceborne living. They passed all their knowledge down to their descendants, who now tend the Vault.
The Vault is /big/. It houses more than 400 occupants, and while conditions are cozy, they're not hopelessly cramped, with conditions more akin to life on a contemporary naval vessel than a space station. Living quarters are in a massive central drum that rotates, giving the traditional centrifugal, artificial gravity. Warrens of chambers and corridors radiating out from the drum's hub house the rest of it all: laboratories, machining shops, and all the places that the Vault's occupants must toil away at to make sure their Vault continues to operate. A pair of accompanying solar power satellites provide more than twice the amount of heat and electricity Orbital Vault G will ever need.
Three things will teach you about Earth: grandpa, books, and the VR machine. The VR machine, accessed via a neural link that all OV citizens are implanted with, is essentially like the Construct from the Matrix. Programs of pre-War life on Earth are often run for children and scholars to learn about how things were. Before the player characters are sent down, they'll be given a full course on pre-War Earth, for all the good that it'll do to help them survive in a post-War world.
OV denizens are not complete strangers to violence. Packs of robotic hunter-killers left over from the War roam the orbital debris fields, their IFF protocols long decayed. OV G has a laser battery and missile rack on either side of the drum, which is used to defend against the threat of crazed HK drones, as well as vaporize bits of celestial detritus that get too close for comfort. The Vault also has a small locker of small arms that has only been opened once since the War. Weapons training is conducted through the VR machine.
What would cause the OV to send a team down to the surface? Why, the wreck of another Orbital Vault, that's what. It came sailing out of the black one day from God-knows-where and tore off the entire east-side warren. Took forty souls with it, too. What went down? Recycling. All of it. Water, air, waste, what have you. Gone, along with half of the hydroponics atriums and half the Vault's anti-space firepower. Fortunately, backup stores survived, and OVF is being generous with its leftovers, but still, unless OVG can rebuild its recycling systems within three months, people are going to start dying.
Other links: Orbital Vault rules and mechanics, Orbital Vault characters