The skull of a Xindi-Avian
The Xindi-Avians were one of the sapient Xindi species. When the six sapient Xindi species fought a catastrophic civil war, in which they destroyed their homeworld.
Although the Xindi-Avians were known to have constructed a fortress on another planet around 800 BCE, when the Xindi homeworld was destroyed it is believed that all of the Xindi-Avians were on the planet at the time. All records indicated that they were completely eradicated.
The Avian fortress was found by the other Xindi and used as a meeting place for the Xindi Council after the devastation of the civil war. The skull of one Avian was kept in the Council chamber.
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The Xindi-Avians are derived from Star Trek.