Sure! Here's a simple game implemented as a single HTML file, using JavaScript and enclosed in script tags. The game is designed for smartphone operation and involves killing enemies to earn points and purchase better swords using pictograms.
Save the above code in a file with a `.html` extension, and you can open it in a web browser on your smartphone to play the game. The game starts as soon as you open the file. Touch or click on enemies to attack them and earn points. The more points you have, the better swords you can buy. The game ends if an enemy touches you, and your score is displayed.