Interesting take on "shell", very cool. Honestly, I found the game boring since only clicking 3 buttons to upgrade things is not appealing to me and doesn't make me want to replay the game to optimize my strategy to make more money. Maybe these types of games are just not for me. I also don't know what the point of the camera is or if its important for anything. If the camera is just for displaying interesting/cool effects at the drill head, it would be cooler to have caves, interesting shaders, lighting, or other interesting scenery/environment art that scrolls by rather than the solid color change plus rocks scrolling by at every shell.