Sure! Here's an example of a simple shooting game implemented as a single HTML file using JavaScript and enclosed in script tags:
This simple shooting game features a player controlled by arrow keys and shooting bullets to destroy enemies. The player is represented by a blue square, bullets are represented by red circles, and enemies are represented by green squares. The objective is to eliminate as many enemies as possible without colliding with them. New enemies spawn randomly at the top of the screen over time. If the player collides with an enemy, the game ends, and an alert is shown with a "Game Over!" message. The game will automatically restart after clicking "OK" in the alert box.