Sure, here's an example of a simple game implemented as a single HTML file using JavaScript:
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In this game, pictograms representing different food items are displayed on the screen. The objective of the game is to click on one of the pictograms, which will then disappear for a brief period of time before reappearing again. The player has to try and click on the pictogram again during this time. The game continues indefinitely with the pictograms randomly disappearing and reappearing.
Please note that this is just a simple example to demonstrate the concept and can be further expanded upon to make a more engaging game.