Shadow monsters

Shadow Persons (also known as Shadow People, Shadow men, Shadow folk or Shadow beings) are said to be shadow-like creatures of supernatural origin which appear as dark forms in the peripheries of people's vision and disintegrate, or move between walls, when noticed. The Shadow People are usually larger than a normal shadow and notably don't resemble the shadow of the person sighting it. They are often reported moving with quick, jerky movements, and quickly disintegrate into walls or...

The Shadow Creature by Eric Jaeger

Bogeyman

Professional project for Casus Belli's magazine. D&D 5 French version.