Sure, here's an example of a game written in a single HTML file that uses JavaScript to create a glitchy cloning effect with emojis:
When you open this HTML file in a browser, it will display a canvas with a single emoji (😀) at the center. Every 0.1 seconds, a clone of the emoji will be created with a slightly increased size, causing a glitchy effect. The clones will accumulate on the canvas over time, creating a trail of emojis. You can modify the emoji, delay, canvas size, or any other aspect of the game to fit your requirements.