1) Wyrd Gods is dedicated to My Lord. This has puzzled readers over the years, and even prompted a few DNSs... The Lord is my husband. (also telepathy is a big thing in Timelessness )
2) In Timelessness, horse is a general term for a mount or a beast of burden. Unicorns, centaurs, and pterippus are real - but not horses. The reasons for this became irrelevant to the main plot during revisions. But the worldbuilding quirk remained.
3) The Dharkan are not part of any mythology. I needed a race...