I have been doing a bit of research on these creatures. Here are some of the things I have found so far:
The Sphinxes were created by Grammaton (According to the fan created Codex Immortalis, another name for Odin) in ancient times. According to other fan material, they were part of the Golden Empire, a pre-Blackmoor realm that opposed the descendants of the Carnifex and were a force for good based on Davania.
In 91 BC, a pair of Sphinxes from Tel-Akbir came to assist the construction of Serraine.
Some known Sphinxes:
- Son of Grammaton: The first Male Sphinx. A master of Wizardry. (PC2)
- Daughter of Grammaton: The first female Sphinx. She was a Shaman. (PC2)
- The Sphinx of Halag (PC2)
- The Sphinx of Kaziri al-Wadi: The Sphinx Al-Kalim consulted (PC2)
- Unknown: A Sphinx in Ylaruam who collects ancient Narval bone carvings from Minrothad, though only if they were at least 500 years old. (PC2)
- Unknown: Two Sphinxes who collect Blackmoor memorabilia. These two assisted the construction of Serraine. (PC2)
- Unknown: A Sphinx who creates Chessmen (PC2)
- Unknown: A Sphinx who collects the Wickerwork of an unknown Ethengar craftsman (PC2)
- Unknown: A Sphinx guarding the tomb of a forgotten Khan (PC2)
- The Tongue-less Sphinx: A villainous Sphinx from Zyxl. Fan created (http://www.pandius.com/mentzerm.html )
Subraces: Although the names Androsphinx (male) and Gynosphix (female) are not used in BECMI, male and female Sphinxes are noted to have differerent abilities. Other subraces from later editions are assumed not to exist on Mystara.
What else is known about Mystara's Sphinxes? Do Sphinxes appear in any modules set in Mystara? Are Sphinxes related to Shedu, Manticores, Chimeras or similar creatures?