Simple and effective, the dream of any game jammer. Good idea, simple to make and polish, easy for the player to pickup and play. Very little to complain here, no design element stood out as badly implemented or unpolished. The way you fight back is, in my opinion, the highlight of game as it is innovative, different and maybe the most important of all, fun. An easy 5 stars in gameplay for you, well deserved! The only "bad" thing I can force myself to find is to say that it has very little content, which is amazing seeing how you have quite a big of different enemies shooting in very different patterns. But variety can be achieved in many different ways, most of which involve having more than a month to make the game. Congratulations, well done!