Sure! Here's a simple open-world game implemented as a single HTML file, using JavaScript and enclosed in script tags:
In this game, you control a player represented by a square on a canvas. You can move the player by touching and dragging on a smartphone or by moving the mouse on a desktop. The player is not limited to any specific boundaries and can explore the open world freely. The player's position is continuously updated and redrawn on the canvas using the `gameLoop` function in JavaScript. The game loop ensures smooth animation and responsiveness.
Note that this is a basic template to get you started with an open-world game. You can add more features, graphics, levels, and interactions to make it a more complete and engaging game.