To secure variation of movable play by achieving the curved movable play with a reduced number of parts.

The self-propelled device 1 of the game machine comprises a rail 4 with curved continuous teeth 2 and a roller traveling path 3; a gear 5 engaged with the continuous teeth 2 to rotate/move; a motor 6 to drive the gear 5; a self-propelled body 7 with the gear 5 and the motor 6 disposed inside; a roller 8 journaled to the self-propelled body 7 to travel along the roller traveling path 3 according to the rotation/movement of the gear 5; and a movable part 9 attached to the self-propelled body 7. The self-propelled device 1 also has a curved sheet-like conductor 10 attached to a rail support part 19, a connection part 11 for feeding the power supply to the motor 6, and a brush conductor 12 one end of which is attached to the connection part 11 and the other end of which extends toward the sheet-like conductor 10 to be brought into contact with the sheet-like conductor 10 while travelling by itself.