Re: Pathfinder, anyone?
Exist in the setting I've built.
Two versions: Human with snake hair, and then the Greater Medusa variety which is the same as the "lesser" version from the waist up, but has the snake lower body.
And I have rules on using both versions as playable races.
EDIT: I probably should explain... The races that have something in parenthesis after them. What's in the parenthesis is the source I'm using. For example, on the Pathfinder SRD, there's two versions of the Ratfolk race, one from Paizo, and one from a third party. This will be using the Paizo version. For the Medusa races and the Reapers, what's in the parenthesis is the title of the book I got the details from. Both are on the store attached to the SRD for 5 USD or less, which is how I got them, although I'm reasonably sure that someone could dig up alternate means for them.