Roddy Piper was pretty good in that film - when he first puts on the sunglasses and sees what the aliens look like, I believe the term “fertilizer face” was used.
I saw John Caprenter interviewed about that movie and he said Piper really wanted to wear shades so he'd look cool in the movie so they added that part about magic sunglasses that could see the aliens. I'm not sure if he said that was Piper's idea, but I think he did. Anyway, it was a good addition, which Carpenter acknowledged.
I remember seeing this as a kid in the 80's as I was a huge pro wrestling fan. The movie was surprisingly good for what it was, and Roddy Piper actually played the role pretty well.
I think the term you are referencing was "formaldehyde face".