Patent ID: 8292746

Claim:
A game system in which one or more common events for a common game are concurrently performed in a plurality of game machines each configured to transmitting and receiving data via a communication line, comprising: a plan management server including: a server time measuring device adapted and configured to measure lapse of system time common in the game system; a plan information storing device adapted and configured to store plan information indicative of remaining time until the system time reaches a process start stage at which a process for each of the common events starts; a plan information updating device adapted and configured to update the plan information stored by the plan information storing device in accordance with measurement by the server time measuring device; and a plan information providing device adapted and configured to provide the plan information to the game machine in response to a plan information request from each of the game machines, wherein each of the game machines includes: an obtaining device adapted and configured to transmit, when a predetermined condition is satisfied, the plan information request to the plan management server and obtain the plan information; a game machine time measuring device adapted and configured to start, when the plan information is obtained by the obtaining device, measuring lapse of the system time independently of the server time measuring device; a stage determining device adapted and configured to determine whether the system time has reached the process start stage or not based on the time measured by the game machine time measuring device and the remaining time indicated by the obtained plan information; and a process executing device adapted and configured to start, when the stage determining device determines that the system time has reached the process start stage, the process for the common event.