Bakhtak

Bakhtak is a ghost or an evil creature that cause Sleep paralysis.

Suffer from excruciating nightmares? Ever wake up with a weight on your chest, unable to move or breathe? That may be the work of the Bakhtak, a creepy being of Persian folklore that sits on your chest while you’re sleeping. No one is quite sure why the Bakhtak takes such glee in filling you with bad dreams or causing ne
ar-suffocation and sleep paralysis, but we do know the Bakhtak gets around. The Bakhtak of Iranian fame is often depicted as a little goblin-like creature, but the same concept takes on the guise of an Old Hag in English folklore and is similar to the "mare" of Scandinavian origin.

Christians have the same thing: Incubus, The male demon of desire and counterpart to succubus! (female demon of desire). Waking up with a feeling of heavy pressure on ur chest is believed to be an Incubus trying to have sex with u while u were asleep!