You may not know this, but only, there is an immensely addictive Shoot 'em up called Boxhead: The Zombie Wars. This game is a great shoot 'em up, which you will get a review document of in the future (Review Documents are found in the review part of the site. Here is my Grort Score on in the level Top Heavy. I got to max times amount (x999) and got this huge score of 254,735,300.