An image-display game system in which at least two image-display game devices are structured such that data communications is possible there between, the image-display game devices each comprising: game program storage means (11, 111) in which a game program is stored; temporal storage means including, at least, a helping item data storage region to store helping item data for helping the game process, and an ID data storage region to store ID data for identifying a player, each of the storage regions being writable with data or readable data therefrom; actuation means actuated by the player for, at least, an operation of performing data communications with another player; communications means (16, 31, 40, 51) for performing data communications with another image-display game device of another player; processing means for carrying out, by said game program, image processing to change an image on display in response to said actuation means; and display means for displaying a result obtained through the processing carried out by said processing means, wherein, said game program storage means (11, 111) includes a helping item data generation program that generates, when one of said image-display game devices and said another image-display game devices are made data communicable by said communications means (16, 31, 40, 51) and when data communications is selected by said actuation means, in response to said ID data transmitted from one image-display game device to said another image-display game device, selected helping item data beneficial for the game process by performing a predetermined calculation based on a bit, selected from the transmitted ID in accordance with a generated random number, the predetermined calculation combining the selected bit with the generated random number, and includes a program for writing the helping item data to said helping item data storage region. game program storage means (11, 111) in which a game program is stored; temporal storage means including, at least, a helping item data storage region to store helping item data for helping the game process, and an ID data storage region to store ID data for identifying a player, each of the storage regions being writable with data or readable data therefrom; actuation means actuated by the player for, at least, an operation of performing data communications with another player; communications means (16, 31, 40, 51) for performing data communications with another image-display game device of another player; processing means for carrying out, by said game program, image processing to change an image on display in response to said actuation means; and display means for displaying a result obtained through the processing carried out by said processing means, wherein, said game program storage means (11, 111) includes a helping item data generation program that generates, when one of said image-display game devices and said another image-display game devices are made data communicable by said communications means (16, 31, 40, 51) and when data communications is selected by said actuation means, in response to said ID data transmitted from one image-display game device to said another image-display game device, selected helping item data beneficial for the game process by performing a predetermined calculation based on a bit, selected from the transmitted ID in accordance with a generated random number, the predetermined calculation combining the selected bit with the generated random number, and includes a program for writing the helping item data to said helping item data storage region.