
1) Cthulhu Mythos species 2) Fictional shapeshifter
Found on
https://www.crosswordclues.com/clue/shoggoth

A shoggoth (occasionally shaggoth) is a monster in the Cthulhu Mythos. The being was mentioned in passing in sonnet XX (`Night-Gaunts`) of H.P. Lovecraft`s sonnet cycle Fungi from Yuggoth, written in 1929–30, and were expounded upon in his novella At the Mountains of Madness (1931). The definitive description of shoggoths comes from the above......
Found on
http://en.wikipedia.org/wiki/Shoggoth
No exact match found.