Sure! Here's an example of a simple 2D shooter game implemented as a single HTML file, using JavaScript and enclosed in script tags. The game has a cartoonish look and includes multiple weapons for the player to use. To play the game, you can tap or click on the screen to shoot at the targets.
This is just a basic implementation to get you started. Feel free to modify and expand upon it as per your requirements. You can add more weapons, levels, power-ups, and customize the visuals as per your game design preferences.