Sure! Here's a simple dragon game implemented as a single HTML file using JavaScript:
In this dragon game, you control a dragon pictogram using the arrow keys on your smartphone. The dragon can move in all directions within the canvas (a 400x400 area). The dragon is represented as a green square, but you can replace it with any pictogram or image you like.
Note that this is a simple implementation to demonstrate the basic game mechanics. You can further enhance this game by adding features such as obstacles, scoring, levels, and more.