Stretch Armstrong
Kenner’s Stretch Armstrong first hit shelves in 1976, and continued in production until 1980. Stretch was a well-muscled action figure, about 15 inches tall, which could be stretched up to 5 feet long. You could pretty much pull and stretch him in all directions and he would conform back to his original shape (with his little speedo).
We punctured ours once, and it was full of some kind of jelly like goop (it was actually some type of corn syrup). The instructions described how you could repair a torn Stretch Armstrong with a bandage, but we tossed those instructions out on Christmas night! On a side note, there was a 1977 version of Stretch called the Stretch X-Ray, which had an over-sized, exposed brain and a transparent body (internal organs were visible).