you pulled out all the stops.
the best thing I think you did in this game is making an individual sprite for each phase of the guns rotation. It was a nice change from having the computer auto-rotate it instead. You also did a nice job putting physics on the little hp boxes. These are all features I've never seen in a flash game before, and combined with awesome graphics and pretty nice gameplay, this is a fantastic flash game, one of the best I've played in years. One little flaw, though, I think there could've been a little more variety between enemies, but besides that, you've certainly outdone yourself.