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A minigame (also spelled mini game, sometimes called a subgame or microgame) is a short video game often contained within another video game, and sometimes in application software or on a display of any form of hardware. A minigame contains different gameplay elements than the main game, may be optional, and is often smaller or more simplistic than the game in which it is contained. Minigames are sometimes also offered separately for free to promote the main game. Some minigames can also be bonus stages or secret levels.
Minigames occur variously as gameplay features, or as time fillers while levels are loading, or as Easter eggs even in non video games e.g. a DOOM-like game or a flight simulator in different versions of Microsoft Excel. In the latter case, they are often called "secret games". In the former case, the successful completion of such minigames may or may not be required to finish the encompassing game. They are often included as extra content to use once the main storyline is completed. Minigames occur also on other forms of hardware e.g. on a dot-matrix display of a pinball machine or even as time filler on a traffic light e.g. StreetPong.
Some games, such as the WarioWare series (which are called microgames in the game), Universal Research Laboratories's Video Action, some Cinemaware titles like Defender of the Crown, David Whittaker's Lazy Jones or the smartphone satire Phone Story are made up of many minigames strung together into one video game. Some similar games, such as Nintendo's Mario Party series, are considered party games, specifically developed for multiplayer. In party games, minigames usually involve performing an activity faster or collecting more of a specified item than other players to win.
The Final Fantasy series is notable for featuring minigames in every entry of the series, ever since the first Final Fantasy (1987), in which a sliding puzzle in the form of an Easter egg can be unlocked while boarding the ship. Considered to be the first RPG minigame, it was added into the game by programmer Nasir Gebelli despite it not being part of Squaresoft's original game design. In Final Fantasy II (1988), a matching game can be unlocked while boarding the ice sled and meeting a certain requirement. Later in the series, Final Fantasy VII (1997) was the first video game to include within it at least thirty minigames, which remains the largest number of minigames for a role-playing game. The PC game Chronomaster featured similar puzzle minigames which were crucial to the plot.
The early Sonic the Hedgehog games on the Sega Genesis had minigame bonus/special stages, such as bouncing around a maze searching for a special gem, or collecting gold rings while running down a tube, and stray from standard gameplay. Sonic the Hedgehog 3, for example, has a special stage in which Sonic must run around trying to touch all the blue spheres, while avoiding red ones, and interacting with other spheres, who have special properties. This bonus stage actually became its own game. By inserting the original Sonic 1 (or Sonic Classics 3 in 1) cartridge into the Sonic and Knuckles lock-on slot, you can then press A, B, and C, then enter any given password to play the special stage corresponding to that password, which plays exactly like those of Sonic 3.
Like above, some minigames become so popular that they are eventually published as individual titles by themselves. Notable examples are Geometry Wars, which was originally a minigame in Project Gotham Racing 2, and Arcomage, a relatively complex minigame, reminiscent of Magic: The Gathering, first introduced in Might and Magic VII: For Blood and Honor.
The PocketStation (for Sony PlayStation) and VMU (for Dreamcast) accessories allowed the user to download minigames from the main console onto the pocket device, and often then sync progress in the minigame back on to the console. Two examples of this include the Chocobo World minigame inside Final Fantasy VIII (which is also playable on PC), and 'Chao Adventure', a minigame in Sonic Adventure.