CTHULHU - THE ART OF RICHARD LUONG by the astonishing Richard Luong More info on the kickstarter project page. This guy is one of the most talented illustrators of Lovecraft’s mythos.*throwing money at the screen*
Shoggoth was a massive amoeba-like creature made out of iridescent black slime, with multiple eyes "floating" on the surface. They are described as "protoplasmic", lacking any default body shape and instead being able to form limbs and organs at will.