I know what this person is talking about

"I have experienced a "full" sleep paralysis episode (with entities) and its no "walk in the park"..."

That is part of a comment on the PuritanBoard on the subject of whether there is alien life on other planets. I think the best answer is there is a lot of demonic activity that can manifest to our senses in various ways, but it has to be pointed out (and nobody at the PuritanBoard pointed this out): since about 2010 there have been over a billion cell phones with easy to activate and use cameras everywhere in the world, and no one has captured images or video of UFOs or anything of a similar nature. In fact, in seems that such sightings, or claims of such sightings, have decreased with the ubiquitous presence of cell phone cameras (add dashboard cameras as well which constantly film a large swathe of sky).

As for full sleep paralysis (with entities)... I like that he said "with entities" because in my case I could only refer to them as that as well.

Full sleep paralysis can happen when you have been awake for an unusual number of hours (40 hours in my case), and then lie down flat on your back. What happens is your body goes into a normal sleep mode, yet your mind is still awake. It is a terrifying experience. You try to scream for help ("mom!!!" in my case, even though I was living in a distant city in my 20s), but your mouth doesn't move because your body is in full paralysis. What I saw when in that state was numerous 'beings' looming over me as if I was being operated on by several doctors. They were in white with faces that had no real characteristics to describe them other than they all seemed to look the same. I was struggling the whole time to come out of the paralysis, and finally did. I wasn't frightened after-the-fact, i.e. I didn't think there were 'beings' in the room or anything like that. Once I had physical control back it was all over.

This happened at a time when I was in an interval going from semi-aggressive non-Christian to reading the Bible and becoming a Christian. I was in conflict with the few people who knew me in that locale and who were angry I was drifting into the Christian realm. For instance, one person who had been in my apartment (actually a section of an old Victorian house) had snatched at a covered book and opened it to find a Bible like they'd caught me in a crime.

Over the years I concluded that what I saw were demons (define demons as you will...fallen angels, the souls of dead giants, whatever). I also experienced good angels in a car wreck that I was saved from. I didn't see any beings during that event, though it was no less real.

Christians need to check themselves when they feel a strong desire to debunk such testimonies because it usually is evidence of a lack of belief in the supernatural in general. Naturalism (materialism, ultimately atheism) can infect one without us realizing it since it is everywhere around us.