This and similar magazines were published by the infamous Myron Fass, the king of the sleazy horror comics in the 60s and 70s. He mixed reprints from defunct pre-code horror comics from such publishers as Harvey and Farrell with some new stuff. The covers were the attraction for those who like this kind of thing: the grosser and gorier, the better.

Fass flooded the magazine racks with all kinds of pulpy crap rip-offs: crime mags, teen mags, rock mags, car mags, war mags, UFO mags... there were dozens of them.

I know b/c I worked at a bookstore back then where we also had the longest magazine rack within sixty miles, and Fass mags multiplied like Russian bots.

Many were one-shots, all were meant to exploit whatever was trendy; he put out a magazine on very cult, every celebrity death, assassinations, you name it. And they were all the magazine equivalent of drinking Sterno. I don't think any of them had color inside; the pages still had chunks of bark floating in it; the stories and photos were either copped from other mags or stolen from aspiring writers, one of whom was a guy who used to come in complaining that Fass never paid him for an interview he'd done with Linda Purl. (I think she was on a TV show back then.) 

Fass was a legend. An @$$hole, but a legend.