Great length, Great Difficulty. Love the story and game play, the only thing I don't like is the final score, you could just keep dieing on level 15 and get a really high final score.
There should be more people, and less missiles, that would make it harder. There should also be more time before it says out of missiles, because I was waiting for one to slide down after my last missile and it made me restart, happened twice.
This game is too easy, you will have to make them bigger for there to be difficulty. 17 and 19 could be medium, but the rest are easy. I do like the idea of a level editor.
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