Xindi-Avians were birdlike Xindi with the ability to fly, although all that is ever seen of this species is a single skull, identical to that of a giraffe. They once darkened the skies of Xindus, the Xindi homeworld. They are thought to be extinct since the Reptilians and Insectoids planted explosives that destroyed the Xindi homeworld after the Hundred-Year War. The Avians, having primitive technology, could not leave the planet and were wiped out. Because of this, the Reptilians say that their lair, in which the Xindi Council now convenes, has a "stench of failure."