Really fun puzzles, and I had a really good "A-ha!" moment early on. Unfortunately, I'm not certain I fully understand the puzzles: sometimes it gets completed and disappears before I can figure out what's going on (when there's more than one number in play still), so I'm not sure what the actual completion goal is. The art is really nice, but it can be hard to quickly read the numbers. I'm definitely keeping this one around so I can give it another shot some time :)