Sure! Here's a playable sample game of a LEGO War Simulator implemented as a single HTML file using JavaScript:
In this LEGO War Simulator game, you control the red LEGO character (player) using the "W" and "S" keys to move up and down respectively. The objective is to avoid colliding with the blue LEGO character (enemy) moving towards you. If a collision occurs, a game over message will appear and the game can be restarted by reloading the page.
Please note that the game logic is kept minimal for this example, and you can extend it by adding more functionalities, levels, graphics, sound effects, etc., as per your requirements.