I definitely liked the art a lot, it's a really cool way of introducing the story! I also like how the dragon gets bigger and bigger, but also gets more health, that's some neat game design. Maybe it wasn't intentional, but the change in direction in the last level made it that little bit harder, because displays aren't as big vertically as they are sideways, meaning there was less space for the arrows to travel and subsequently there was less time to react.
My only gripe with this game is that it can get a bit repetitive if it would've been longer, and the visibility of the arrows was really bad! Black on dark green, black on dark blue, I really felt stressed that I couldn't see the arrows.
But besides that, good submission! Also like the little story that accompanies the game.