They were a technologically advanced species and created many strange and powerful devices. Some of their technology was left scattered across the Unknown Regions after they were gone, and the legend of their technical prowess was known to traders in the region as well. They were said to have created an entire world, which was the source of these bits of technology, though almost no one in the Unknown Regions used them. They created cures for deadly diseases, as well as small devices that allowed users to communicate over vast distances. They also built a hidden space station, which was similar to the design of some hyperdrives.
After their extinction, an organization called the Guardians was brought together to protect the advanced technology that they left behind. Though they were once a proud and honorable organization, over thousands of years they grew corrupt and greedy, jealously guarding the secrets of the Xaxax. They looted the artificial world the Xaxax had created, stealing all they could. The Guardians also split up the power core of the Xaxax's space station, using one of the pieces to power their largest ship. They used the space station as a center of study, as well as a vault to keep their stolen artifacts.