Three thousand nine hundred years before the Imperial Era (2120 CE in the Earth calendar) a Telsavran criminal organization invaded Earth, enslaved most of the population, and took many Humans off world. During the three hundred year occupation, the Telsavran altered Human DNA and created the Duarga. A stronger, more heavily built version of Humans, more suited to be slaves and warriors. Their great strength and endurance made them good warriors, which the Telsavran could use for war or entertainment in their gladiator blood sports.

Physically strong, their high density bones and muscles make them heavier than water and they cannot swim without a flotation device. Duaraga are fully mature in about fifteen years, and have an incredible appetite during growth phases. Their external body plan is exactly the same as Human, and they retain Human emotional stability. Humans and Duarga can, and often do, engage in intimate relationships, but the genetic changes made to create the Duraga, mean they are not interfertile. Humans and Duarga gametes are not compatible, so partners cannot concieve children naturally.

Aside from the higher density bones and muscles giving Duarga great strength and endurance, there is little difference between Humans and Duarga. Societies and life perspectives are virtually identical, though most outside observers argue the Duarga are friendlier. Duarga strength and endurance allow them to carry a load, equal to their weight, and walk an average of five kilometres per hour, for twelve to fifteen hours. They can carry a load half their weight and jog at fifteen kilometres per hour for five to six hours. They can run at full speed (thirty five to forty kilometres per hour) for up to fifteen minutes. They can run at full speed carrying a load equal to half their weight, but for a shorter time.