This one is just bloody terrifying full stop. Monsters hiding in closets or under the bed are a thing of nightmares for most kids. A skeletal type monster with crazy hair would definitely terrify me as child.
I've had all of these, most commonly the corner ghost (or giant Shelob type spider in one terrifying episode) but asphyxiation was the worst by far. Started when I was around 6 years old, only discovered what it was a few years back.
Sleep Paralysis-I experience this every so often and I just learned from my Psychology professor that it does no harm. Just want to spread the word in case others that suffer from it don't know what it is.