Shoggoths are large, amorphous and amoeba-like. They can form mouths, eyes, and various appendages at will. They were genetically designed by an ancient race of alien life on Earth. Originally aquatic in nature, the shoggoths learned to live on land and eventually destroyed their ancient masters.
“We were on the track ahead as the nightmare plastic column of foetid black iridescence oozed tightly onward through its fifteen-foot sinus; gathering unholy speed and driving before it a spiral, re-thickening cloud of the pallid abyss-vapour. It was a terrible, indescribable thing vaster than any subway train—a shapeless congeries of protoplasmic bubbles, faintly self-luminous, and with myriads of temporary eyes forming and unforming as pustules of greenish light all over the tunnel-filling front that bore down upon us," -H.P. Lovecraft, At the Mountains of Madness
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