Sure, I can create a simple game using JavaScript and enclose it in script tags within a single HTML file. Please find the code below:
In this game, you control a player pictogram using touch input on a smartphone. The goal is to avoid colliding with the enemy pictogram. If a collision occurs, an alert box saying "Game Over!" will be displayed.
Note that you will need to provide the actual pictogram images (player.png and enemy.png) and update the respective image sources in the JavaScript code accordingly.