very fun game. I had assume more people would have done this type of game given the theme, but you were the first i played with this style of game. I would have liked the goal up front, and more explanation what each upgrade did. I will say the quickest way i found to get gold was to dig down then boost up (which i assume was on purpose). My only major complaint was that the word "core" broke the 4 color rule (not that it really changes the game).