This was Rick Baker’s first creation for a *cough* real movie back when he was a youngster. He also wore the suit, ala Paul Blaisdell. You knew the kid was likely to become a pro when he whipped this suit out, again his first major gig, and then suggested to the producers that due to his deficiencies it be kept mainly in shadows, much like The Thing in The Thing from Another World. However, the producers were instead amazed at how good the suit was for the pittance they’d given Baker, and they showcased it mercilessly, shooting tons of close-ups of its immobile face in broad daylight.
Once back when my youngest brother was just like six or seven, I found him watching this on TV. The cast had gone out hunting for the creature, but never found him, and were returning wearing and discouraged to their RV. My brother piped in that the monster would pop out of the RV and attack them. I explained how this was impossible, because the monster would never be able to manipulate the push-button door handles with his big, awkward tentacles. Just as I was going through this spiel, they opened the trailer door and the monster jumped out and attacked them. My little brother turned to me and, to my well-earned humiliation, laughed in my face.
I learned a valuable lesson that day.