Open world
There is no consensus on what the earliest open world game is, due to differing definitions of how large or open a world needs to be. Ars Technica traces the concept back to the free-roaming exploration of 1976 text adventure game "Colossal Cave Adventure", which inspired the free-roaming exploration of "Adventure" (1980), but notes that it wasn't until 1984 that what "we now know as open-world gaming" took on a "definite shape" with 1984 space simulator "Elite", considered a pioneer of the open world; Gamasutra argues that its open-ended sandbox style is rooted in flight simulators, such as SubLOGIC's "Flight Simulator" (1979/1980), noting most flight sims "offer a 'free flight' mode that allows players to simply pilot the aircraft and explore the virtual world". Others trace the concept back to 1981 CRPG "", which had a free-roaming overworld map inspired by tabletop RPG "Dungeons & Dragons". The overworld maps of the first five "Ultima" games, released up to 1988, lacked a single, unified scale, with towns and other places represented as icons; this style was adopted by the first three "Dragon Quest" games, released from 1986 to 1988 in Japan.
Labyrinth: The Computer Game
"Labyrinth" was the first adventure game produced by Lucasfilm, which became a critically acclaimed and commercially successful developer in the genre. The game's technology and mechanics influenced the company's subsequent title "Maniac Mansion", whose "SCUMM" engine was reused in many Lucasfilm adventure games. The word wheels were a predecessor to that game's point-and-click interface. Gary Winnick, an artist for "Labyrinth", went on to lead the production of "Maniac Mansion" with Ron Gilbert. Fox contributed to "Maniac Mansion" as well, and he later directed Lucasfilm's "Zak McKracken and the Alien Mindbenders". Retrospectively, writers for the Australian Broadcasting Corporation regarded "Labyrinth" as a solid first attempt, but as inferior to "the real classics" made afterward by Lucasfilm.