Everything can be explained away through science. Most people who say this man appeared to them within their subconscious visions tend to leave out the fact that they already had prior knowledge on him through posts on the internet. Whenever you already have an image of that dark, benevolent, noire entity in your head, your brain forms him into "reality" whenever you're going through a terrifying hallucinogenic experience such as sleep paralysis or when you're tripping on DPH.
These things are powerless. Conjured up by the brain. Fear something real. Fear the God above us. Save yourself for Him.