Definitely a neat little puzzle game! The undo button was definitely a great choice to add, especially on the 6th main level. It took me a while to set everything up and then I botched the ending, thankfully that mechanic is there to aid in that!.. If only I noticed beforehand, whoops. Admittedly I also ended up using the wait function a lot, the room for error isn't that big in most cases. Also, the audio is very well done. Other than that, it's a neat spin on a classic puzzle game!