Shoggoth

thingiverse

Shoggoths are massive, shape-shifting creatures made up of a pliable, amoeba-like substance that's incredibly malleable. They have the ability to grow whatever organs or appendages they need in order to accomplish their goals, and in their usual state, they're a squirming mass of eyes, mouths, and wriggling tentacles. At one time, Shoggoths were under the control of a more powerful species, but they've since risen up against their former masters. Although they've been largely wiped out, some still linger on - often in the darkest depths of the ocean. Shoggoths could also be adapted for use as an attacking sea plant, and while they're perfectly at home in the water, they can also move around on land.