The Ur-Quan Kzer-Za are one of the two races of the Ur-Quan species. They share many physical characteristics with their Ur-Quan Kohr-Ah brethren, except that their skin is green rather than black. Their race was genetically engineered by the Dnyarri from the main-line of the Ur-Quan species during the height of their slave empire. The Kzer-Za were designed to be the "thinkers": the scientists and overseers of the Dynarri slave empire.
The Kzer-Za follow the Path of Now and Forever. This doctrine states that they must seek out all sentient life and offer them two choices: annihilation or subservience to Kzer-Za rule. A species is allowed to chose the way they will serve the Kzer-Za. They may serve as a combat thrall species, whereby they are allowed some autonomy of action including the right to travel through space. Alternatively, a species may chose to become a "fallow" species; these species are forced to live on their homeworld beneath an impenetrable slave shield. The punishment for stepping out of line is annihilation, either for the individuals responsible, or, if the crime is particularly egregious, for the entire species as a whole.
Currently, the Kzer-Za are involved in the Doctrinal Conflict. It is an agreement between themselves and the Kohr-Ah, whereby both species move in opposite directions across the galaxy, promoting their doctrine upon the worlds they encounter. When the two races meet, they engage in a war to determine which doctrine becomes ascendent and lays claim to the ancient Sa-Matra, a Precursor Battle Platform of immense power.