The Unknown Race is a concept that existed in Old Age Canon.
Most of information about this in New Age is unclear/undecided yet.
The Unknown Race created the races of Vilous, for reasons unknown. They may have had contact with the agudners long ago. The sergals are sometimes said to be their “perfect chimera beast” and their greatest or favorite creation. It is likely that they shaped the world of Vilous to fit their whim, as it is very unlikely the world would have only had one continent otherwise.