Sure, here's an example of a simple shooting game implemented in a single HTML file using JavaScript and pictograms:
In this game, you control a player character (represented by a square) using the left and right arrow keys. Pressing the space bar fires a bullet (represented by a thin rectangle) upward. The goal is to destroy the enemies (also represented by squares) that gradually descend from the top of the screen without letting them collide with the player. The game keeps track of your score, which increases each time you hit an enemy. If an enemy collides with the player, the game is over and your final score is displayed in an alert.
Note: This is a basic example and can be further enhanced with additional features and visual improvements as per your requirements.