This game is a great concept and can be very rewarding at times. The downside is the unreasonable requirements to make it through levels and open new machines. I have been playing daily for over 2 months now and still barely have made it into the second world. I dont normally leave reviews on games, but seriously they need to do something to improve the speed of advancing. Again, over 2 months of daily play and still getting the measly 7 day reward bonus only.