As pointed out, the platformer engine is not smooth, and the controls are... well, not great. But if you get past this little things, you have a pretty deep game with great mechanics that really deserve to get a try. I personally loved it, it's fun and pretty much complete as a whole. You and your game, sir, deserve more votes and comments! I'd love to see this concept extended :) (I'll admit I have a kink for mining game with resource management)
Some ideas to make the game even cooler: * metrics system to see how deep we are (or some other stats) * unified treasure/gems system, so i can buy whatever I want * infinite (or at least larger) map ? * went to the bottom, but there were nothing special. an end game would be cool but I suppose you ran out of time * upgrades
I liked mining mechanics and that gems are dropping to the ground and are not collected automatically when you mine.
Sound was laggy though, and platformer engine is not very smooth.