Based on the 1972 comic, "Swamp Thing", filmed in 1982 was another movie that I embraced in my youth. I first saw it on Cinemax when I was 9 years old. In a nutshell, the movie involves a tree-hugging scientist who's experiment goes seriously wrong.
Other than my uncle's constant cat calls in reference to Adrienne Barbeau's large breasts, the scene that I remember most, is a character named "Ferret" played by David Hess, having his skull crushed by the Swamp creature's hand. The budging of the eyes and the sight of blood running down his face from the creature's fingers was quite awesome...especially to a kid.