The Future is Now.

In the Year 2121, Aliens known as the Necroids began invading the Earth. Much of its military was defeated before they even put vehicles on the ground. Eventually, a final decision was made to evacuate the Solar System.
The Ships eventually found themselves landing in The Odin Star System. Odin is a very large star, a blue dwarf a hundred times larger than Sol. The Odin system is much larger than our solar system, being about over 150 light hours across and holding multiple habitable worlds.
The ships landed on the planets, and started the slow process of rebuilding. They encountered alien races on many of these worlds, and grew with them in relative harmony.
As technology advanced, interplanetary communication and travel is now a very practical thing. Interplanetary corporations have begun to spring up, and space has been turned into a new frontier.

However, with this, bandits and pirates have begun to crop up, taking advantage of undefended trade routes and settlements. As such, some of the planetary governments met up and decided to found a new government for the entire star system. They are called TWR. They were initially successful for a while, but for various reasons, their popularity has waned dramatically. Reasons include their expansionist policies, expansion of machine rights, protection of companies that are rather unpopular for their own reasons, the list goes on.
Eventually, a few bandits decided to take advantage of this fact and have become more politically motivated. By marketing themselves as 'heroes of the common folk', they have been able to form a giant criminal empire, and now, they have nearly a monopoly on crime.



Factions:


ACE:
ACE is the only name in organized crime. Their biggest market is selling stolen good on the black market at a mark-down. They have almost no competition, as anyone who 'threatens their turf' is hunted down. One of their trademarks is their sense of honor: for various reasons, they generally try to limit their targets to 'richer people' and do give away charitable donations to 'disenfranchised groups'. They also have restrictions on conduct, to limit how destructive their crime is.



TWR:
The government. Contrary to what some would say, they are hardly a police state. They're a constitutional republic founded on the protection of individual rights, and to that end they'll go to pretty extreme lengths. However, there are complaints here and there. One of the big ones being that they're too overbearing. For example: Most schools have at least one combat drone patrolling them (though they're armed with non-lethal weapons). They're also seen as protectors of the economic elite (technically true; however, that's simply because people keep stealing from the rich).


Both groups usually display some mutual respect for each other, despite there being an official conflict going on. As far as most of them are concerned, it's nothing personal. In fact, they'd even be willing to cooperate in some situations. For example, if they encountered:



Necroids
Necroids are a...'race' of aliens. Well, 'race' isn't the right term, perhaps. Nobody's actually sure even if they truly are sentient: They never talk or display signs of having a culture. Their technology is mostly biological with implanted technology. Their ships are essentially giant 'organisms' with smaller entities inside. Their invading forces as well are odd biological constructs. Said constructs however, are not 'truly alive'. They tend to lack important features such as a reproductive system or a digestive tract, or even a brain at times. They also lack any kind of emotion, memory, or even basic survival instincts. They're also excruciatingly hard to kill. Walking nightmares, they are. Luckily, they are very rare.





Technologies and weapons and such:



Melee Weapons:
Despite this being the future, there are multiple melee weapons still in use. In fact, due to advances in technology, they're really quite deadly.
One the spectrum of bladed weaponry, the cheapest and most common are your standard knives. Sometimes people will also carry bigger steal blades, as well. The most advanced and powerful bladed weapons that PCs can start out with are Synthium blades. Synthium is a synthetic crystal. It's very bullet proof substance, allowing the user to block smaller bullets with it. The substance can cut through concrete like cork.
Similarly, the most powerful blunt weapons PCs can start out with are also made of synthium.
Even more powerful than Synthium blades are 'sonic blades' which vibrate in an attempt to cause resonance, making their cutting power even better. However, the best 'bladed' weapon would be the plasma blade, which can cut through nearly anything.



Land Vehicles:
There are several types of Land Vehicles in use right now. The Cheapest would be things like peddle bikes. However, a real pilot would generally prefer a motorcycle over that or a cool, fast car.
The most powerful land vehicle PCs can start out with would be an armored car with a weapon turret on top.
Tanks are also still commonly in use, the most advanced of which being Planetary Assault Tanks, which resembles this: http://www.fantastic-plastic.com/LunarT ... BagArt.jpg
However, the most powerful land vehicles are Mechs. Mechs are 10-25 foot tall vehicles with legs instead of wheels or treads. If you like, you can start out with a mech if you give it some kind of weakness.



Air and Space Vehicles:
Don't call them the Navy! The navy is for water!
There are 3 types of spacecrafts: SpacePlanes, SpaceBoats, and Mobile Stations.
A SpaceBoat is similar to a helicopter or a hot air balloon. They're able to hover in one spot and stay there a while. They are also generally easier to land than a SpacePlane. They're also usually better at carrying cargo or passengers than SpacePlanes.
SpacePlanes are extremely fast and quick. They fly in, drop bombs or shoot at a target and then quickly fly off. Most of them require a runaway or something similar to land and take-off.
Mobile Stations are what they sound like: Mobile Space Stations about the size of a city. They're almost universally incapable of landing on a planetary surface and surviving. They also often act as carriers for smaller spacecraft.


Firearms and Slugthrowers:
Normal Firearms are still in use. The cheapest and most common firearms are small 'squirrel guns' like .22 pistols. However, more powerful weapons exist, such as scoped hunting rifles and single shot guns. The most powerful firearms PCs can start out with are smaller paramilitary-grade weapons like Assault Rifles, Sniper Rifles, and Combat Shotguns.


Energy Weapons:
Energy Weapons have a few advantages over slugthrowers. One is that they usually store more ammunition, as batteries can store more energy than clips can store bullets. Another is that many of them cause secondary effects, like lighting a target on fire or freezing it or giving it radiation poisoning (depending on the type of weapon). They're usually non-lethal (unless their secondary effect is inherently lethal). Their biggest downside is that they have very significantly less stopping power than firearms.





Races:

Humans:
Humans make up about half of the system's population. They're technologically the second most advanced species to operate in the Solar System.


Robots:
sentient Machines are exactly what they sound like. They're usually humanoid, and are able to emulate human emotions and behaviors. However, they're at the bottom rung of the social ladder, and most groups consider them to be property rather than people. TWR is hoping to expand their rights, but so far they haven't reached an agreement with their voters.


Aliens:
There are several non-human races in the Odin System. Each colony began mingling with local cultures, causing them to adopt aspects of the other's culture. Alien tribes are often bought out (peacefully) by various organizations and are usually assimilated into Human cultures (by their own choice). At the highest level of TWR's government, Aliens have the same rights as humans. However, many smaller governments (municipal, mostly) will try to turn them into second-class citizens. They are still doing better than Robots, however.
Aliens have mixed views on TWR. Some of them dislike that their fellow aliens are fleeing their native cultures for human ones, while others consider the relative prosperity inside the Colonies. All of them resent being made into second-class citizens, but there are aliens that think that it's worth it in the long run.

List of types of Aliens:

The Demetrians: Green skinned aliens with antennas. They have compound eyes in the place of normal eyes. They live on the very jungly planet of Demeter. They're the tallest sentient organisms in the system, standing up to 9 feet tall (Though the average height is 7 feet tall). However, their limbs are very thin and spindly, so they're not any stronger than humans. They are very agile, though.

((More coming soon-ish))