U.S. Patent No. 4,738,451: Multi-player, multi-character cooperative play video game with independent player entry and departure

Issued April 19, 1988, to Atari Games Corp.
Priority Date May 20, 1986

U.S. Patent No. 4,738,451 describes the gameplay of the Gauntlet series, where multi-players navigate a maze. Gauntlet was a four-player dungeon crawler. Each player would select a fantasy troupe with unique abilities. In the first Gauntlet, each player was forced to take a different troupe, but in Gauntlet II, everyone in the party could be wizards if they desired. The players would need to cooperate with each other to escape. Progress could only be made if the players move together since all the characters must remain visible on the screen. Locking the camera with all the characters created a competitive cooperation feeling in the game. Even though all the players had to progress through the maze together, each player could independently control their character on the screen. There were game items the players could obtain to help their journey, but only a limited number of items are available to the players must choose who gets what. Players could also join or leave the game at any time. This patent was reissued in 1996 which we covered here.

A multi-player, multi-character video game where the game rules force the players to cooperate in negotiating the maze at least until the characters reach a portion of the maze where a specific objective is located. Certain limited resources to change the attributes of the characters or to increase their longevity are displayed in a maze. The players may compete to obtain possession of these limited resources when the characters have cooperated in their movements sufficiently to move to the location of the limited resources. Cooperation among the characters is forced by forcing all characters active in the game to remain visible in the displayed window. Players may enter the game at any time, and they may leave the game at any time without affecting the status of the game or the status of the other characters in the game. All active players may simultaneously, independently control their characters so long as they do not attempt to move their characters outside the currently displayed window.

Illustrative Claim:
1. A video game comprising: a central processing unit; a video display; a plurality of sets of controls coupled to said central processing unit; sofware means run by said central processing unit and coupled to said controls, and to said video display for reading player input from said controls and generating, storing, changing and outputting data for causing said video display to display a maze populated by a plurality of different kinds of characters each having attributes, said maze also being populated by a plurality of attribute-affecting entities including monsters, each said character having attributes including longevity and abilities including the ability to fight and to move, said attributes defined by stored data, said longevity attribute defined by stored data and decreasing over time and when that character is damaged by a monster, and including means for displaying different types of resources having characteristics defined by stored data and displayed on said video display throughout said maze in quantities and loctions established by said software means, said resources increasing the longevity attribute or otherwise affecting the attributes of the first character which is displayed to have obtained possession of them, and for causing said video display to display action by said characters and said monsters in accordance with rules of said game implemented by the following included means: first means for allowing a plurality of players to each simultaneously and independently control the movements and actions of one of said plurality of characters in the video game via said controls; second means for allowing any one of said plurality of players to enter the game at any time and simultaneously and independently control the movements and actions of one of said characters independently of when the other players started playing or when any other said player or players stops playing; and third means for encouraging the players to cooperate during play by displaying on said video display only a window portion of said maze which is related to the relative positions of all the characters being active in that they are controlled by a player at that time and by not allowing any active character to move outside the bounds of said window portion and by moving the window portion to display different portions of said maze only so long as all the active characters are contained in said window portion.

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