not bad
Interesting idea and good gameplay. But you should improve a bit with your level designing. The first 20 levels were like a walk in the park and you hit a brick wall hard. I completed the game so the 5 last levels weren't too hard, but looking back at my experience this game felt like 20 levels of tutorial and 5 levels of actual gaming. So if you make a sequel you should distribute the difficulty a bit better. Other than that, good job.