From Overview:
They fall from the desert depths in ones and twos. As with the first drops of a monsoon, they herald a mighty storm on the horizon. And, once the waters have passed, all that once stood will have been washed away.
The ryonth are a plague upon all races. A parasitic race of desert-born slavers, they view themselves as the rightful rulers of all. The ryonth hold none as allies, only tools. They ravage and consume all things they encounter, leaving desolate wastes in their wake. The race’s ability to bond with other creatures, draining these mounts in the process, fuels the fears of ryonth infestation.
Sages do not know the origin of the race. But it is easy to see their place in the nightmares of any culture. Many are the forgotten civilizations buried by the desert sands, le