2. Medusa
With the producers planning on bringing in characters from varying sources, we could see them going down the route of involving classical mythology into the show's own mythos. Heroes, gods, goddesses, it could literally involve anyone and one of our favourite sympathetic villainesses should make the bill: Medusa. Far from the venomous character she portrays, we could easily see a different story emerging - a woman cursed by Regina to turn every man she meets into stone, seeking redemption in her trapped life. It'd be an interesting take on an old favourite, continuing a theme of the show that not every monster wants to be a monster. It's a role we could easily see filled by a guest star recommended by regular and heroine Jennifer Morrison (Emma) - Rose Byrne, the seasoned actress easily capable of giving both the iciness, chill and venom of Medusa's image and the broken, frightened woman within.