The fero xyn existed naturally within the Yuuzhan Vong galaxy. In common with all living things connected to the Yuuzhan Vong, the fero xyn did not have any link to the Force. The Shapers of the Yuuzhan Vong took the genetic components of this creature and merged them with those from the vornskr, ultimately producing the voxyn.
A poison analogous to that of the voxyn was expelled by the fero xyn.