The Thing - Shoggoth.

Currently rewatching the Thing prequel and a thought struck me, if you remove the footage of the ship in trouble and crashing from the start of the first film it wouldn't be too big of a stretch to assume that it's actually Old Ones archeology and the alien is a shoggoth. Add the occasional cry of 'Tekeli-li !' when the creatures attacks, and away you go ! 😊