Extremely difficult game that unfortunately lacks the satisfaction of other similarly unforgiving games.
The game is so frustrating because if you get a jump off by even a small fraction of a second you will mess up and either miss a gold bar or die. And there are no lives; you start from the beginning of the level when you mess up.
Even when after dozens of tries you finally get the timing right and get to the bonus stage, one mistake and you have to restart and the the entire stage perfect again! The bonus stage is even harder than the normal stage, so completing even a single bonus stage would take an unimaginable degree of mental fortitude.
Despite these core annoyances, the game has its own charm and will likely have a small cult following as a result. The voxel graphics look really pretty and suit the game style nicely. The music beats seem to be largely the same throughout the progress I've made so far, and is pretty catchy.
This game is not for the meek. I am not sure it is even that well suited for gamers who love punishing games. Upon finally completing a level the satisfaction you get seems lacking, probably because its based on trial and error timing and not skill. I would recommend Super Meat Boy and Dark Souls for gamers who want satisfaction AND challenge.