Incomplete List of Races:
Imps: One of the members of the physically imposing precursor race developed a mutation which altered HGH, making it a mental stimulant which could enhance magical and paranormal abilities. This one was bred with others, and the descendants became a new precursor race with mental abilities. When enough of his descendants had inherited the ability, they began to inbreed the descendants to try and maximize this mental enhancement. This lead to a physically small race of beings with powerful telekinetic powers.
The inbreeding, however, had caused an extremely high miscarriage and infant mortality rate, so during the time while they were being inbred they were altered to have high fertility rates to offset this fact. The high fertility rate was found to be useful to the other races, and these began to use Imps as breeding stock. In time the diversified gene pool stabilized the miscarriage and infant mortality rate, leaving them as a meter tall group of humanoids, usually with claw, fangs, and/or horns, possessing a high fertility rate and powerful telekinetic abilities.
Goblins: Some groups of early Imps were not bred with other races, however, in time, the inbreeding increased the birth rate further, making the miscarriage and infant mortality rates less significant. These early Imps formed small communities which battled each other. Their gene pool eventually stabilized somewhat by breeding with captured humans and demons, but the small size of that gene pool led to there being little diversity among them. When Homo sapiens began having contact with them, generally through war as they were too hostile for standard relationships, they called these tribes Goblins, and treated them as an inferior version of Imps.
