That's pretty cool. I like the idea of a defense-like game where you have little minions that you have to help out to achieve the goal rather than being directly hands on with it. Well done!
The little day and night cycle lighting effects were pretty sweet, too. Only things I'd suggest is maybe (unless I missed it?) a way to fast-forward to night time when you are "ready" rather than having to wait, and maybe some less cheery music to match the frantic mood.
Well done!