[lch]

The Gorgon stems from greek mythology, that's right, but so do most of Pangea's units: Pan, Centaurs, Satyrs, Minotaurs, etc.

The civilised part of greek mythology seems to have become Arcoscephale, while the chaotic wild life, the monsters and fables, have become Pangea. As such, I see no problem that something that the greek saw only as witches and monsters cannot be a pretender of Arco, but only of Pangea.