(Sparkypants Studios) When I read the short story Tower of Babylon by Ted Chiang I just had to put down the book and start working on an image. It was really inspiring. In his story he described people living on the tower spending their entire lives ferrying food, bricks, and mortar up to the next level where they were passed along. This sparked the idea of a game where the player would gather resources and combine them into materials to race upward toward the heavens constructing their own tower. To add challenge we put in "enemies". Bugs and plagues that would slow or stop the player's progress.
This video shows the unity proto in a state where bugs attack from below and fly down to the base to destroy the tower. The enemy turrets on the tower are how the player defends their construction.