Sure, here's an example of a simple game where you slice and level up a stickman to become a god, with endless enemies. Please note that this implementation is just a basic example and can be expanded and improved further.
To play the game, you can copy this HTML code into a single HTML file and run it in your web browser, preferably on a smartphone for touch interaction. The game starts automatically and you can tap on the enemies to slash them. As you level up, more enemies will appear, and if an enemy collides with the player, the game is over. Score and level are displayed on the screen. Click anywhere on the screen after game over to restart the game.