Sure, here's a sample implementation of a game called "Metal Royale" using JavaScript within a single HTML file:
This implementation sets up a basic game framework for "Metal Royale". It includes a canvas element to display the game, event listeners for player movement using the left and right arrow keys, and a game loop that continuously updates the game by clearing the canvas and drawing the player on it. In this example, the player is represented by a red square. You can add more game logic, such as enemy characters, power-ups, and scoring, to create a complete game experience.