Sure, here's an example of a simple snowball game implemented in a single HTML file using JavaScript:
This code sets up a canvas element and allows you to control a snowball emoji using arrow keys on a smartphone. The snowball moves left and right, and the emoji is drawn using a pictogram if supported by the browser. Otherwise, a circle is drawn to simulate the snowball. The game runs in a continuous loop, constantly updating and redrawing the snowball's position on the canvas.
Note: The availability of pictograms is dependent on the browser and operating system being used. Some browsers may not support pictograms as fillText, in which case a circle will be drawn instead.