If I might make a suggestion, aside from the construction that this is a pretty common idea; it does have decent sound effects, and the graphics are a little stout. However, there is one problem I have run into a few times and I'm still on the first collection - When I fire a shot, it gives little time between before the enemy fires. Now what I'm suggesting is that if you're to do another project like this, make sure you allow time before the opponent fires.