Nicely done! Please keep working on this; I'd like to see more!
The game tells me I've won, but I don't feel like I have.
I think I've reached the end? When I finish the fourth wave it loops back to the first again.
Can't say for certain. Maybe about an hour. You really ought to add a message that says "Congratulations! You broke the game!"
Oops. I broke it.