Strange and unexplained phenomena. Maybe there are lights that float around at night with no obvious source. Or there are sudden cold spots in the middle of a warm day. These things can make the character in the story feel like there is something otherworldly and menacing present. In addition, the presence of strange, unidentifiable creatures that seem to be watching from the shadows would add to the horror.
Well, perhaps in a story set in mt khtadin, there is an old abandoned house. The locals say it's haunted. A group of adventurous teenagers decide to explore it one night. As they enter, the doors slam shut behind them. They start to hear eerie whispers and see fleeting apparitions. The floorboards creak as if something is following them, and they soon realize they are in a place of pure horror.
The sudden apparitions are really scary. Just imagine you are walking on the mountain and suddenly a figure appears out of nowhere.
Words that describe a menacing presence, such as 'stalker' or 'lurker'. They make the reader feel like there is something dangerous and unseen nearby. Also, words that play with the senses, like 'stench of death' or 'the deafening silence of the graveyard'. These descriptions can be very effective in creating a horror atmosphere. And words that suggest a loss of control, like 'ensnared' or 'trapped' can add to the horror as well.
Supernatural elements. Old legends and local superstitions can add a spooky touch. Maybe the spirit of an ancient tribesman who was wronged and now haunts the land. It could appear as a wispy figure in the middle of the night, making strange noises and causing unease.
The strange whispers in the forest are spooky. They make you feel like there are unseen presences watching and trying to communicate something sinister.
The unknown is the scariest. In '2 horror story', often things like strange noises in the dark where you can't see what's making them are terrifying.
One of the scariest elements could be the unexplained noises. For example, the sound of creaking floorboards in the middle of the night when no one is walking. Another would be the cold spots. You walk into a room and suddenly feel an icy chill that seems to seep into your bones. And then there are the apparitions. Maybe a shadowy figure that you catch a glimpse of out of the corner of your eye, but when you turn to look directly, it's gone.
Since I don't know the 'the horror truck story' well, generally in horror stories involving trucks, the large size and power of the truck can be a scary element. It could be used to run over people or chase them in a menacing way. Also, if there is something hidden in the truck like a monster or a dead body, that would add to the horror.
The sudden and unexplained behavior. Like when it activates on its own without any prompt. It's really scary when a device that's supposed to be under your control starts acting up on its own.
The most frightening element could be the feeling of being trapped. If the stairs lead to a dead - end or a place from which there's no escape, that's really terrifying.