Sure, I can help you create a simple scary game using JavaScript within a single HTML file. Here's an example implementation:
This game sets up a simple scenario where you control a player (represented by a walking pictogram) by moving your mouse on a webpage. Your goal is to avoid colliding with a ghost (represented by a ghost pictogram).
If the player and ghost collide, a scream pictogram is displayed, indicating a game over.
Please note that due to the limitations of text-based characters, the scare factor might be limited. However, this implementation should provide a basic game experience. Feel free to modify and enhance it as per your requirements.