Cool game! I liked the concept quite a lot and it connected well to the theme. The only thing is that being forced to place blocks one by one slowed the pace down too much in my opinion, and not being able to change blocks means that if you mess up, you have to start all over from the first block. I think a less frustrating way to go about it is to just let the player place all the blocks first. I still had fun playing though. Nice job!