Sure! Here's an example of a game called "Circle Illusion" implemented as a single HTML file using JavaScript and enclosed in script tags:
In this game, you'll see a canvas with a circle in the center. Every time you click inside the circle, your score will increase. The score is displayed at the top left corner of the canvas. The game runs for time intervals of 1 second. Once you click anywhere inside the circle, the score will increase by 5. The objective is to get as high a score as possible within the time limit.
Please note that this is a basic implementation, and you can modify and enhance it further according to your preferences and specific requirements.