During my third year of college we had a character study project, which involved a miniature model of the character and a latex mask.
The character I chose was one of the fish-like deep ones from HP Lovecraft's "The Shadow Over Innsmouth".I chose this because, without a proper description, I could take liberties with the design.
The model is sculpted in Sculpy, with a plaster base, and the mask was sculpted in clay and then moulded in plaster and cast in latex.
The design of the character went through many iterations, from a angler fish / man hybrid to the strange deep sea creature it became in the end. Experience with miniature modelling greatly helped me here as I could quickly shift and change details to see what worked best.
The color palette and texturing was mocked up in photo shop, using reference images from deep sea creatures.