Really nice, I really like the sound effects. I managed to hit two bats with one stick through, I'm not sure if that was an intentional feature but it was cool
cute art for the characters. One critique is that it wasn't clear at first if the stick damaged the bats since they take a second after being hit to start fading away. If they started to fade away instantly then that would improve the feedback to the player.
Overall really nice job on this game