Stranger Things was the science fiction darling of 2016. Its Spielbergian plot along with charming acting made it loved by many, but its subtle use of practical effects—seen most effectively in the show's most mysterious baddie, the Demogorgon—was simply masterful.
This brief behind-the-scenes video from shows that the showrunners didn't have to add much to this monster to make it scary. It's pretty terrifying all by itself.
Who knows if the Demogorgon will make a reappearance for the second season of Stranger Things, or if there are more awesome monsters still lurking in the Upside Down. Seeing the amazing work behind the Demogorgon, I'm hoping for the latter.