I'm currently thinking about a good antagonist for a story. A scary one to be correct. Me and my friends tend to agree that non-physical beings (such as ghosts) freak people out the most.
To my opinion, a disfigured humanoid creature is the most scariest. The fact of making a disfigured humanoid creature into an apparition makes it scarier since physical power has no effect.
My friends are scared of little girls that are ghosts. Examples such as the grudge and the ring.
So my question is: What physical features or activities of a creature scares you the most?