This was super cool! Love the look of it, and the death anim feels very satisfying when you find them. (I found the download plays better than the browser version, i kept having my camera reset in browser).
I do wish there was a way to restart if you run out of bullets and get game over. Also... I kept wanting to go into previous room to compare. I found the 1st room to be the most difficult only because I was less familiar with the room... so being able to go back to that first room might've helped.
Overall, this concept is really neat!