Surprising
Much better game than I suspected and submitting the score actually works - unlike 80% of the games on Newgrounds, who just seem to have a dummy button. The controls are astonishing smooth and I couldn't find any glitches. Graphics looked good and the instructions, as well of the whole point of the game were easy to understand. The characters behaved different, so there is actually a deeper sense in switching through them. Your Practice Mode was a great idea, too. Sound effects and bgm weren't too importunate.
The only thing that bugged me was that there seems to be only one level for all the waves.
All in all a great engine and a good concept, it just gets old too fast.