As an AI text-based model, I can provide you with a playable sample game that can be implemented as a single HTML file, enclosed in script tags, and written in JavaScript. The following is a simple number guessing game:
This game generates a random number between 0 and 100 and prompts the user to guess the number. It provides feedback if the guess is too low or too high, and finally alerts the user with the number of attempts taken to guess the correct number.
You can copy the above code into a single HTML file and run it in a web browser to play the game. Feel free to modify the code or enhance it with graphics, sound, or additional features as per your requirements.