Cool concept for a game! I like the simplicity of the art style, so you can focus on the core gameplay of it, and the overlay effect that was used helped establish the setting. The white box's color depleting as it loses health was a great choice! The controls and movement itself was pretty intuitive, I like the you have to reload the gun occasionally instead of just non-stop shooting. Unfortunately my biggest criticism for this game at the moment is the difficulty. I tried several times to get past even the first level but it proved to be a big challenge. This is mainly due to the first enemies shooting far too fast. And there feels like very few windows in which you have a good chance to attack them. The entire game closing after you die too is a bit of a hassle. But I think if you make those necessary changes, the game is a good package as a whole.