The anonymity. When you don't know who is sending the texts, it creates a sense of unease. You can't put a face to the threat.
The feeling of being watched. Just like in the stories where the texter seems to know the person's every move. It's like there's no escape from this unseen observer. For example, when the texts describe things that only someone close by could know. Also, the sense of helplessness. If the police or others don't believe the person getting the texts, they're left to deal with the horror on their own, which is really terrifying.
The unknown sender is a really scary element. When you don't know who is texting you and they're sending threatening or creepy messages, it gives you a sense of being targeted by an invisible enemy. For example, getting texts from a blocked number.
A woman received texts from someone who claimed to be watching her all the time. Everywhere she went, she got a text about it. It was terrifying.
The unknown is the scariest. In 'as is horror stories', things are often left in their natural state, so you don't really know what's lurking in the shadows or what's causing those strange noises. It's that sense of not having all the answers that makes it terrifying.
Isolation is also a key element. When characters are alone in a spooky place, like an abandoned asylum in one of the stories. They have no one to turn to, and that makes the situation even more terrifying as the horror unfolds around them.
The unknown is one of the scariest elements. When things are not clearly defined, like a strange figure in the fog in some stories from '1001 horror stories', it makes our imagination run wild. We start to create the most terrifying scenarios in our minds.
The scariest element could be the sense of the unknown. For example, in many stories, there are strange noises or happenings that the characters can't explain. It's that not - knowing what is causing the fear that really gets to you.
The isolation in many of the stories is really scary. Like when a character is alone in an old, abandoned building, cut off from the outside world, and they start to feel like they're being watched by something malevolent. There's also the fear of the supernatural, such as ghosts or demons that defy the laws of nature. This makes the characters, and the readers, feel powerless against them.
The sudden movement of the LPS toys when they're not supposed to be able to move is really scary. It goes against what we know about them as inanimate objects.
The unknown and the supernatural. Take the Black Shuck for instance. A huge, black spectral dog just appearing out of nowhere is terrifying. There's no rational explanation for such a thing, and that's what makes it so spooky in UK horror stories.
The loss of control. When someone is hypnotized, they are in a vulnerable state. In horror stories, this often means they can be made to do things against their will, like harming themselves or others, which is really scary.