Human - Every day average joe.
Dream Construct - A creature of the dream (or nightmare) given physical form in this world.
Nightmare - A creature that lives in the dream and is affiliated with the nightmare.
Dreamling - A creature that lives in the dream and is affiliated with the dreaming.
Mythos - A mythological creature that lives in the physical world and has human form.
Subraces of Mythos:
Immortal - A mythological creature that has lived so long in human form that it has forgotten (or it has been forgotten) what it once was. Generally these are agless beings, or creatures that age very slowly. Their true heritage may be any sort of creature. Almost all true creatures are in this class, and exceptions must be taken up with staff prior to approval or character conception.
The following are a list of subraces that may be taken, and are applicable to a human with a relation to the named mythos, in any traceable amount. Generally, once it gets past the stage where a mythos is a great-great-great grandrelative, the blood is not strong enough to have much of an effect (if any) on the person. The closer the relation, the stronger the connection with the spirit world, dream, or etc.
-Werefolk (these are humanoid enough to still exist as per normal in human society, if they are careful.)
-Vampires (these are humanoid enough to still exist as per normal in human society, if they are careful.)
-Pegasus/Centuar/Other Equine creature
-Other (Accepted only with prior staff approval and a full writeup of the creature desired.)
Remember, with the exception of Were-creatures and Vampires, this is only a blood relation to said creatures. The character will have been raised as a human, will look like a human, and with the exception of perhaps abnormal talent or two, will consider themselves human. Very very few Mythos are lucky enough to know what sort of creature they are, but those with close enough blood may feel as though they were born in the wrong sort of body.
Anything I forgot, guys?