One of my favorites so far haha. The progression was really fun for me! Rather than progressing mechanically, I felt like each night I learned something new about the zombie behavior to exploit in my next day's build. It was fun trying out different designs, especially trying to design differently based on each gun. My initial designs I tried to make a base to hide in but was quickly overwhelmed and had to kite them. Then I tried a tower but again they were able to jump up so I had to jump off and run away. Then I tried pitfalls to take them out with the shotgun. Finally I moved on to getting them to line up a certain way so I could take on waves with the sniper. Even as the game is, I could see myself spending a long time on this (I had to tell myself to stop so I could get back to rating all the games)