Yep, even if you look in the Hexen resource lumps, you'll find that the game itself was referred to as "Heretic 2."
And as most of you already should know, Korax was supposed to be the serpent, and the heresiarch the rider. Hence, the heresiarch should have been the "serpent rider."
I have no frickin clue why they decided to digress from the plot though. <!-- s:roll: --><img src="{SMILIES_PATH}/icon_rolleyes.gif" alt=":roll:" title="Rolling Eyes" /><!-- s:roll: -->