The game will aim for some degree of verisimilitude, as in "hard science fiction," but will have a humorous tone. I'm going to avoid things like psychic powers, but flying toasters will count among your foes and you will heal your wounds by pouring HP sauce on them.
It is some unspecified future era. Mankind has established colonies throughout the solar system, in space stations and on other planets and moons. At least, the planets and moons that have anything worthwhile going for them.
Cybernetic, genetic, and nano engineering is commonplace. In addition to a wealth of other applications, this has let to human engineering that has branched mankind into four general races. Races as in kind you pick at the start of the game when creating your character.
- Baselines; also known as standard humans. They're probably better fed and generally more fit than early 21st century humans though.
- Androids; people who have replaced their bodies with mechanical bodies of metal, plastic, and diamond. There's no mind-uploading; the closest thing that exists is "crystallizing" a brain by replacing its flesh neuron by neuron with artificial matter until the brain becomes something that can be plugged in to a robot body. Some androids think they're the next step of human evolution and can be jerks about it.
- Morphs; these people are biological, but they've modified their bodies into a variety of exotic forms. A morph can look like anything from monsters to cartoon characters. Some make fun of morphs for their tastes in physical forms. Morphs are also my game's answer to "rubber forehead aliens."
- Sprites; these people live in deep space and have engineered their bodies explicitly for zero-gravity environments. They now look like classic arcade game sprites like space invaders and Pac-Man ghosts. Since most of my actual game will take place on a planet, I was thinking of some kind of anti-gravity for Sprites, though I haven't come up with a satisfactory way to explain or at least justify the anti-gravity yet.
Humanity on Earth has grown relatively conservative in the future, so the majority of baseline humans exist on Earth while the other branches of humanity live in the rest of the solar system. Earth itself has an overall "second world" status following a cold war between Earth and its colonies. The current "capital" of humanity is on Mars.
The economic decline of Earth has allowed various regions of it to become breeding grounds for sophisticated criminal syndicates that rival large companies and small countries. These syndicates would later expand to the rest of the solar system's underbelly, allowing space pirates to exist.
Several decades ago, before many of Earth's colonies were established, before the technology that led to mankind branching into its four forms existed, Earth was wracked by strife (I haven't decided if it was an actual world war or not). In this tense era of conflict a private organization built a colony starship and sent it to a nearby star. The people on this starship were never heard from again.
Today, it has been announced that faster-than-light travel has been invented (like the Sprite's anti-gravity, I haven't come up with any satisfactory science or pseudoscience to describe what this FTL tech is like). For its first application, an FTL starship has been built to travel to the star that lost colony starship was sent to, to discover the lost interstellar colony's fate.