The Alpha Primitives are a slave race created by the Inhumans, first appearing in Fantastic Four #47 (February 1966).
The former king of the Inhumans called The Unspoken revealed that Alpha Primitives are actually humans who have been exposed to gas created from Xerogen Crystals, a substance created by the Kree as a weapon for the Inhumans to use against their human enemies [REF].