Madman (1981) | HORROR/SLASHER | FULL MOVIE

At a summer camp for youths, cockey pre-teen calls out the name of mass serial killer "Madman Marz". Suddenly, counselors are being maimed and slaughtered in various ways by the backwoodsman who has returned when his name was called.

IMDb: https://www.imdb.com/title/tt0082696