Its a casino game in which the Minecart (or coin) that you enter in the coin slot, rolls around until you put the lever in the down position. When that happens, if it is one side of the track, when you put the lever back in the up position, the minecart will burn in lava. However if it is on the other side of the track, when you put the lever back in the up position, the game will reward you with a Diamond!