The Centhraki or "Horse People" are a race of horse headed people native to Nidsk and some surrounding lands. They have bodies exactly like humans, except for their heads and feet, which are like those of horses. Traditionally, they were an exclusively tribal people, living a hunter gatherer lifestyle and worshiping primitive deities. When Nidsk was first colonized by people, many skirmishes broke out. The Centhrakis' stone tools were unfortunately no match for the bows, swords and axes of the invading humans, and the majority of the Centhraki were wiped out.
Since those days, there have been efforts by the humans and Centhraki at reconciliation, and certainly there are no more wars between the two peoples, but there is still an air of enmity, and blatant racism among some. Biologically, the Centhraki seem to have the genetics of humans with some genes replaced by genes from horses. Who or what perpetrated this genetic engineering is unknown, but not having an SE Field, the Centhraki are assumed to be of the Advanced Artificial evolutionary type.