Sure! Here's an example of a simple horror-themed game implemented as a single HTML file with JavaScript:
In this game, you control a player character (represented by a pictogram) on a black background. The player character can be moved using the arrow keys on a smartphone. Each arrow key press updates the player's position, and the player's position is then displayed on the screen using the `transform` CSS property.
You can replace the `src` attribute of the `<img>` tag with the actual path to a pictogram image of your choice for the player character. Additionally, you can further extend the game by adding horror-themed elements, sounds, and interactions.