Taking aim at the course of the snail in Red or Green , drop a token. In case, a token goes into the Red course, two steps will be advanced. In case, a token goes into the Green course, one step will be advanced. But, if a token goes into the Black course, the game will be over,then the player lose whole steps which are gained. The player can receive the tokens gained by depressing a "DROP" button. But, on the other hand, the player can continue the game trying for the advanced steps.