GAME SYSTEM, CONTROL METHOD FOR GAME SYSTEM, GAME CONTROL DEVICE, AND PROGRAM

PROBLEM TO BE SOLVED: To provide a game system for a user to set easily a game data group conforming to the strategy of the user.SOLUTION: A replacement candidate setting unit 134 sets, as a replacing candidate, at least one of a plurality of pieces of game data which are member candidates of a game data group. A replaced candidate setting unit 136 sets at least one of a plurality of pieces of game data which are members of the game data group as a replaced candidate. A replacement execution unit 138 changes the member of the game data group by exchanging the replaced candidate into the replacing candidate. An attribution information setting unit 140 sets the attribute information on the game data group on the basis of the members of the game data group. A changing information display control unit 132 displays the change information relating to the change in the attribute information on the game data group, which is caused by the replacement by the replacement execution unit 138, before the replacement by the replacement execution unit 138 is executed.