Below is an example of a simple game implemented as a single HTML file using JavaScript and emoji pictograms. The game is designed for smartphone operation.
Emoji Game
Try to avoid getting stabbed by clicking on the emoji!
In this game, the player's objective is to click on the emoji to avoid getting stabbed by a knife (represented by another emoji). When the player clicks on the smiling face emoji, it briefly changes to a moved knife emoji, simulating the attack, and then reverts back to the smiling face after a second. Please note that this is a very basic example and can be expanded upon to create a more complex and enjoyable game experience. However, it gives you an idea of how you can implement a game using JavaScript and emoji pictograms in a single HTML file.