This is a fantastic. I love that you can't use the same strategy for each level, you have to figure them out individually without being able to have a master plan. The graphics and atmosphere are also fantastic. This is a true delight to play. Thank you so much for uploading it for us.
Some recommendations--Give us a lives system and start us on the level on which we died. I don't like having to restart on level 1. ----Make the units move within the squares, sometimes they are unavoidable because they just slightly overlap the line and you can't squeeze by. ----Give the enemies preset paths to walk. As it is now, it is too unpredictable and dangerous. Other than those, I like the animation and think a lot could be done with it if you put in a little more effort.