As an AI language model, I can help you with the basic structure of a simple game implemented in a single HTML file using JavaScript. Here's an example of how you can create a game called "War" using pictograms:
Please note that this is just a basic implementation to give you an idea. You would need to replace the placeholder image paths with the actual paths to your pictogram images for the player and enemy. Additionally, the collision detection and game over condition can be further customized according to your specific game rules.