Horror comic covers can be quite explicit but the best often suggest rather than show the terror. One of the best techniques for this is the shadow. The artist gives you a suggestive outline but not the full monty. In a small group of tales, the monster is actually a shadow. These stories date back to stories like A. Merritt’s Creep, Shadow (Argosy, September 8- October 20, 1934). George R. R. Martin used the idea in his Song of Fire and Ice, with the Red Witch giving birth to such fearsome progeny.