Sure, I can help you with that. Below is an example of a simple game called "Chicken Bandits" implemented as a single HTML file enclosing JavaScript within script tags:
Chicken Bandits
Click on the chickens to catch them!
In this game, some chicken pictograms are displayed on the game board. Your goal is to click on as many chickens as possible within 30 seconds. Each click earns you a point. Once the time is up, an alert will display your final score.
Please note that in order to make this game work, you would need to have a chicken.png image file in the same directory as the HTML file.