Pretty nice idea. It was a simple but fun game. Art and music fit very well and gave a nice atmosphere. The only thing I would suggest is making mining animation faster. Long mining animation gave the feeling that the game is not very responsive. Maybe I'm wrong and it's not animation's fault, but I feel like making it a bit faster, the game would let you press the space button faster, because now if you press it too fast the game counts it as the wrong action.