Shoggoth (concept art and locomotion):This is a giant mass of semi-liquid protoplasm that can create and absorb organs at will. Unlike the formless spawn, the Shoggoth rarely grows limbs, teeth or mouths, instead relying on their sheer size to crush and absorb prey.
Starspawn (concept art, mature wing anatomy and regeneration process):
The Starspawn of Cthulhu are the original dwellers of R’lyeh but most (if not all) are inactive (“dead”) since the sinking of their city in the south Pacific.
Their younger form has no differentiated legs and primitive wings, but is about the size of a whale and possesses cognitive and psychic skills beyond any human. Their ability to form mitotic cysts to regenerate makes them specially resilient.