Action history writing means (92) of a game device (10) writes, into storing means (80), in a game being executed, action history data indicative of an action history performed by a specified character (62) among a plurality of characters (62). Action history condition determination means (94) determines, in the game being executed, based on the action history data, whether or not any one of a combination of a current action of the specified character (62) and one or more previous actions of the specified character (62) and a combination of a plurality of actions of the specified character (62) satisfies an action history condition. In a case where it is determined that the action history condition is satisfied, action control means (96) causes a character (62) to act based on action information associated with the action history condition.