U.S. Patent No. 5,390,937: Video game apparatus, method and device for controlling same

Issued February 21, 1995, to Square Co., Ltd.
Priority Date July 16, 1991

U.S. Patent No. 5,390,937 (the ‘937 Patent) describes the active battle system found in games like Final Fantasy IV or Chrono Trigger. Traditionally, RPG’s used a turn-based battle system, where each character has to wait for their turn to attack.  Turn order is based on who has the highest agility or speed stat. The active battle system, as described by the ‘937 Patent, scrapes the traditional turns for constant action. Player characters and enemies can attack at any time in an active battle system. A timer governs when each character may attack. The active battle system creates a dynamic feeling compared to the static nature of a turn-based system. Players must choose their next move wisely because of the unpredictable nature of when the next attack will occur.

Disclosed in a video game of enhanced realism in which actual combat is closely simulated. The game is so adapted that an enemy character on a display screen may launch an attack against a player character on the same screen, even while the player character is in the process of inputting a command, at elapse of a set time period specific to the enemy character. The attack is made without an interruption in the flow of time of the game.

Illustrative Claim:
1. In a video game apparatus in which a player character and an enemy character are displayed on a display screen of a display unit and the player character and enemy character carry out attacks on each other in accordance with an inputted action command or a predetermined action schedule, a method of controlling the video game apparatus comprising the steps of: clocking a time, which has been stipulated for each character, from the end of a previous action of a character; generating a signal for character when the time clocked in said clocking step is equal to or greater than a predetermined time assigned to that character; allowing, in response to said generated signal, input of an action command if the character is a player character, and processing in accordance with the inputted action command; and processing, in response to said generated signal, an action in accordance with the predetermined action schedule if the character is an enemy character.