As a language model AI, I can provide you with a basic sample game implemented as a single HTML file using JavaScript. Please find below the code:
In this simple space exploration game, you control a spaceship represented by a blue circle in the center of the screen. Your goal is to discover planets represented by gray circles around the canvas. By clicking on a planet, it becomes discovered and changes color to green.
To play the game, you can copy the above code into an HTML file and open it in a web browser. The game canvas will display a white background with the spaceship in the center. Clicking on undiscovered planets will change their color to green, indicating they have been discovered.
Note: This is a basic example and can be further expanded upon to include additional game mechanics, levels, and features based on your specific requirements.