Game device, game control method, and game control program for controlling game in which player's character located in game field is manipulated

1. A game control program embedded on a non-transitory computer-readable recording medium, comprising:

a module configured to move a player character in a game field in accordance with a control command from a player;

a module configured to move a character belonging to a group, which includes the player character, along with the player character;

a module configured to move an enemy character located in the game field so as to follow the player character or the character belonging to the group;

a group control module configured to cause at least one of the characters belonging to the group to leave the group;

a target control module configured to change a target of attack by the enemy character, from the player character or the character belonging to the group to the character that left the group, when at least one of the characters belonging to the group is caused to leave the group by the group control module;

a module configured to allow the enemy character to attack the player character or the character that left the group when the enemy character catches up with the player character or the character that left the group; and

a module configured to return the character that left the group to the group when a predetermined time has elapsed since the character left the group without the character being attacked by the enemy character.

2. The game control program according to claim 1 , further comprising: a module configured to cause another character located in the game field to join the group.

3. The game control program according to claim 1 , wherein the target control module ensures that the character that left the group is no longer attacked by the enemy character when a predetermined period of time has elapsed since the target control module changed a target of attack by the enemy character to the character that left the group.

4. The game control program according to claim 1 , further comprising: a module configured to cause another character located in the game field to join the group.

5. The game control program according to claim 1 , wherein the target control module ensures that the character that left the group is no longer attacked by the enemy character when a predetermined period of time has elapsed since the target control module changed a target of attack by the enemy character to the character that left the group.

6. A game device, comprising:

a character control unit configured to move a player character in a game field in accordance with a control command from a player;

a group control unit including a processor configured to move a character belonging to a group, which includes the player character, along with the player character; and

an enemy character control unit configured to move an enemy character located in the game field so as to follow the player character or the character belonging to the group,

wherein the group control unit includes a function of causing at least one of the characters belonging to the group to leave the group,

wherein the enemy character control unit changes a target of attack by the enemy character, from the player character or the character belonging to the group to the character that left the group, when at least one of the characters belonging to the group is caused to leave the group by the group control unit,

wherein the enemy character control unit includes a function of allowing the enemy character to attack the player character or the character that left the group when the enemy character catches up with the player character or the character that left the group, and

wherein the group control unit returns the character that left the group to the group when a predetermined time has elapsed since the character left the group without the character being attacked by the enemy character.

7. A game control method executed by a game device, the method comprising:

moving a player character in a game field displayed on a display device in accordance with a control command inputted by a player via an input device;

moving a character belonging to a group, which includes the player character, along with the player character;

moving an enemy character located in the game field displayed on the display device so as to follow the player character or the character belonging to the group;

causing at least one of the characters belonging to the group to leave the group;

changing a target of attack by the enemy character, from the player character or the character belonging to the group to the character that left the group, when at least one of the characters belonging to the group is caused to leave the group,

allowing the enemy character to attack the player character or the character that left the group when the enemy character catches up with the player character or the character that left the group, and

returning the character that left the group to the group when a predetermined time has elapsed since the character left the group without the character being attacked by the enemy character.