Here's an example of a simple horror game called "Mr. Hopp's Play House Horror" implemented as a single HTML file using JavaScript. It uses pictograms for a smartphone-based gameplay experience.
To play the game, simply copy the entire code and save it as an HTML file (e.g., "game.html"). Then, open the file in your favorite web browser. The game will display a text-based interface where you can enter commands like "investigate", "open door", "look around", "turn on light", or "hide" to progress through the game and experience the horror in Mr. Hopp's Play House.