Pretty fun game - my biggest problem is that everything in the game feels very slow and there isn't much you can do during the waves themselves. I got to the flying enemies once, but after losing, the thought of having to go through the slog of the first 10 waves again was enough to put me off the thought of continuing. I think you could do some interesting things with this concept, and for a first gamejam this is great! Definitely playable and has some entertainment merit.