|This article may contain material discouraged by the guidelines for video game subjects. (June 2012)|
|Sid Meier's Civilization IV|
|Publisher(s)||2K Games & Aspyr|
|Director(s)||Sid Meier (creative)
Michael Gibson (art)
|Producer(s)||Barry Caudill (senior)
Jesse Smith & Dan Magaha
|Designer(s)||Soren Johnson (lead)
Mark Cromer (lead audio)
Michael Curran (sound)
All Firaxians (additional)
|Programmer(s)||Mustafa Thamer (lead)
Soren Johnson (AI)
|Artist(s)||Steve Ogden (lead)
Brian Busatti & Mark Shahan (lead modelers)
Dorian Newcomb (lead animator)
Sven Dixon (UI)
|Writer(s)||Paul Murphy (lead)|
|Composer(s)||Jeffery L. Briggs
|Release date(s)||Microsoft Windows
June 30, 2006
|Genre(s)||Turn-based strategy game, 4X|
|Mode(s)||Single player, multiplayer|
|Media/distribution||CD (2), DVD (1), download|
Sid Meier's Civilization IV (also known as Civilization 4 or Civ4) is a turn-based strategy, 4X computer game released in 2005 and developed by lead designer Soren Johnson under the direction of Sid Meier and Meier's studio Firaxis Games. It is the fourth installment of the Civilization series. Civilization IV was released between October 25 and November 4, 2005, in North America, Europe and Australia.
Civilization IV is a turn-based game in which the player builds an empire from very limited initial resources. All standard full-length games begin in 4000 BC with a settler who builds a single city. From there, the player expands an empire while contending with rival nations, using the geography, developing infrastructure and encouraging scientific and cultural progress. By default, players can win the game by accomplishing one of five goals: conquering all other civilizations, controlling a supermajority of the world's land and population, being the first to land a sleeper ship in the Alpha Centauri star system, increasing the Culture ratings of three different cities to "legendary" levels, or by being declared "World Leader" by winning a popularity election through the United Nations. If the game's clock runs out (by default in the year 2050 AD) with none of these goals fulfilled by any nation, the nation with the highest score is declared the winner.
The game's first expansion, Warlords, was released on July 24, 2006, in North America and July 28, 2006, in the European Union. A second expansion, Beyond the Sword, was released worldwide between July 18 and July 30, 2007. A remake of Sid Meier's Colonization, based on a total conversion of the Civilization IV engine, Colonization, was released on September 23, 2008.
As of March 26, 2008, Civilization IV has sold 3 million copies, according to Take-Two Interactive. The game was re-released along with both of its expansions in 2007 in an edition entitled Sid Meier's Civilization IV: Complete; the American version of this compilation was released on May 12, 2009, in a DRM free package that contains the core game, the two expansions, and the 2008 Colonization remake.
Civilization IV is a turn-based 4X game, in which the player leads a civilization from a small tribe to conquering the world over several millenia. Conquest can be done in at least four ways: diplomatically being declared the world's leader, using military to defeat all other civilizations, becoming technologically superior to the other players, or to win through expansion of the civilization's culture across the world. Additionally, the game scores each civilization based on a number of factors, and victory can be had if the player's civilization score far exceeds any other, or if at the end of a limited-turn game, the player has the highest score. The game can be played as a single player facing against one or more computer-controlled opponents, or through online multiplayer games alongside computer opponents.
At the onset of a game, the player determines how the world map will be generated, either loading a pre-defined scenario, or specifying a number of parameters, including player counter, climate, and landmass type, for a randomly generated map. Players can then select one from 18 specific civilizations, or allow the game to select one for them randomly; these civilizations are loosely based on actual nations in mankind's history, and give the player a leader avatar, an initial set of technology, and unique units that that civilization can build. The player also can set the difficulty of the computer-controlled opponents prior to the game. When the game starts, the player and opponents are randomly located across the square grid map. Most of the map will remain dark to the player until they move units close enough to a space to see what is there, trade with other civilizations for their map, or acquire technology that reveals the map to them; further, the game uses a fog of war that unless the map space remains in sight of a player's units for that turn, the contents of that space are not shown. Each map space has a terrain type, such as plains, tundra, or desert, that affects what resources can be obtained from it, movement rate of units through it, and possible special resources that can be extracted from it.
Each turn, the player has the ability to move any units a number of spaces based on their movement rate and terrain, including attacking enemy units, instruct certain units to take specific actions, adjust the governing of each city they have settled, initiate diplomatic contacts, and review their current status. The player starts with a single military scouting unit and a settler unit, which is needed to found a city. As the player's civilization expands, they can found more cities and expand their military.
Units and combat 
Most units that the player can generate are military units that have a combat strength and movement rate. Certain units have specific bonuses that come into play if they are attacking or defending a certain terrain type. Each unit can gain experience through combat, and when they achieve experience levels, the player can assign the units a new bonus, such as improved strength or terrain bonuses. Most units are land-based, but later in the game with progression in the technology tree, the player can obtain ships and planes that can carry units over sea or air to destination spaces.
Combat is initiated by moving a military unit onto the space occupied by an opposing unit, including those stationed in cities. Combat is resolved based on the statistics of each unit along with random chance, making it possible for weaker units to defeat stronger ones. Defeated units are removed from the game; if an attacking unit removes the last defending military unit from a space, it will move to occupy that space, and if that space was a city, then the attacker will have captured that city. The player has the option of razing an occupied city or installing a new government and bringing that city into its civilization. Any number of units can be stacked onto a single space and move as a group if so assigned, though when attacking, the overall combat phase is resolved by one-on-one unit battles.
In addition to combat, military units can be set to fortify a specific space, perform sentry duties around a specific area, destroy enemy city improvements, or can be set to auto-explore the map.
Non-military units include settlers used to found cities; workers and work boats used to improve land and water spaces, respectively; spies which are invisible to others and can perform covert operations in opposing cities; and religious missionaries that can spread religion in a target city.
Throughout the game, the player may have a chance to generate a "Great Person", including Great Generals (military), Great Scientists (technology), Great Artists (culture), Great Prophets (religion) and Great Merchants (monetary). These units, named after historical figures, can be used for one-time boosts in various ways. A Great General provides bonuses for units that it is grouped with in attacks, while a Great Scientist can be used to either discover a new technology immediately or construct a special building that produces a good amount of research points. Building certain wonders or discovering certain technologies will improve the chances of generating a Great Person. However, as units, they can be attacked and captured before their use.
Cities, buildings, resources, improvements, and culture 
Once a city is founded, it will extract food, material, and monetary resources from nearby spaces, the number based on the population size of the city. Food resources are used towards city growth, while material resources are used to construct either new units or buildings/facilities within the city that alter how the city operates or may have other benefits to the player's civilization. The game will automatically allocate which spaces are used and how the resources within a city as it grows, but the player is free to manage the city directly. This can be used to turn a part of the population into one of several specialized occupations, at the expense of having one less space that can be used for resources for each specialist. These specialists instead can generate additional research, culture, or money from the city. Additionally, one can simply assign these specialists as idle, helping to generate happiness for a city. This may be necessary to counter unhappiness generated by military units, a larger war, a lack of special resources, or the like; a city that is unhappy may fall into a brief period of rioting where no production will occur.
Each city can produce one military unit or one building at a time, the rate determined by the amount of material collected from surrounding spaces. After researching the right technologies, the player can "hurry" production using the civilization's monetary coffers to produce the unit the next turn. The player can queue up a number of units and buildings which are then produced sequentially as the previous one is finished. Optionally, the player can simply devote the city's resources towards producing research, culture, or money.
Buildings range across a number of functions; early buildings include granaries that help to boost the city's growth rate and barracks that provide initial experience bonuses to military units, while later in the game, buildings such as airports, drydocks, and factories can made. There are also a number of special buildings that can be constructed. One type are World Wonders, of which only one across all civilizations can be constructed. Constructing these typically take a good deal of time but also provide a great benefit to the player's city or civilization. There are also National Wonders, of which only one or two can be building within each civilization. The availability of buildings is tied to the player's progress on the technology tree.
As the player expands their technology tree, they will uncover special resources on the map. Some of these are necessary for building certain units or improvements such as horses for horseriders and chariots, and oil for machinery units like tanks. Others are considered luxury resources, like ivory, cotton, or wine, and can be used to improve city happiness or as trade goods in diplomacy. These resources cannot be accessed until the proper terrain improvement is made by a worker unit for that tile. For example, a corral is needed for obtaining horses, while a plantation is required to get cotton or wine. Other terrain improvements can be made on spaces that lack these special resources as to boost the space's production for the city that controls it: farming can improve food production, while mines can increase resource availability. Roads, and later railroads, help to increase movement rate and to create trade networks between the player's own cities as well as with opponent cities.
Through buildings and specialists, each city generates culture that contributes both towards the area that the city can influence and subsequently use for resources, and the overall civilization's cultural value. If there are two opposing cities near each other, the cultural values of each city will influence which space is controlled by which city; it is possible that a city close to an opponent's city will want to join the opponent's empire if the cultural influence is strong enough.
Technology, government and religion 
Once a city has been founded the player can select a technology from the game's technology tree to research. Each technology requires a number of research units to reach before it is discovered, upon which its benefits are immediately seen by the civilization. Most technologies have pre-requisite technologies that must be discovered first - for example, the player must know bronze working before they can learn iron working. The player can select a future technology, with the game then queuing all intermediate technologies to reach that. Technology development is necessary to being able to build new types of units, buildings, and improvements. Ultimately at the end of the technology tree are technologies to develop a colony ship to reach Alpha Centauri; being the first to launch such a ship assures a technology victory.
Within the technology tree are both government civics and religion technologies. When one of these are discovered, the player has the option of then changing their current government civic or state religion to this new one; though offered immediately after the discovery, the change can later be done at any time. These civics and religions have certain benefits that affect the whole civilization. If the player opts to switch, their entire civilization will have one turn of anarchy while the government switches over.
Religion plays a larger role in the game as well. Each city is tracked as to what religions it has adopted; adoption can come from when the religion is first founded, or through the use of missionaries that can spread religion from one city to another. This can be both beneficial and detrimental depending on what civics and religion the player is currently using; for example a city that has the same religion as the state religion can be more productive, while non-state religions may increase unhappiness within a city. Such missionaries are not limited to the player's civilization and can spread the religion to opposing civilization cities.
Once a player has met another civilization, they can perform diplomacy at any time. If the two civilizations are on friendly terms, the player may wish to extend a trade, which can include a lump sum of money, a regularly allocated payment over time, units, luxury resources, technologies, or even cities. Optionally, the two may wish to simply share their current world maps or offer open borders that allow the other's units to cross their territory freely. The player can also request that the civilization go to war against a third civilization. On the other hand, warring civilization may attempt to negotiate a cease fire, or make strong-arm demands from the other civilization.
|This section may need to be rewritten entirely to comply with Wikipedia's quality standards. (June 2012)|
- See also: Music in Civilization IV
- The game's soundtrack features compositions of Medieval, Renaissance, Baroque, Classical, Romantic and Minimalist origin, and contemporary by Jeff Briggs. The 2011 Grammy Award winning song "Baba Yetu" was composed specifically to be played at the start of the game. The title means "Our Father" in Swahili, and the song itself is a rendition of the Lord's Prayer. It is performed by Stanford University's Talisman A Cappella and was composed by Christopher Tin.
- Each leader has a unique piece of music played during diplomacy (with the exception of Kublai Khan and Genghis Khan who share music).
- Narrative voice acting is provided by Leonard Nimoy, who reads a quotation related to a technology when it is discovered. Land-based units also offer short phrases in their culture's native language when selected. If the player's view is near a city, they will hear sounds related to the nation which owns that city.
- Great artists visually resemble famous people, such as Elvis Presley and William Shakespeare, even when they are not given those names. The "create great work" button for the Great Artists is a picture of the Mona Lisa.
- Sound effects are played when certain buildings or improvements are built, such as coins jingling when a bank is completed. Ambient sounds can also be heard near different terrains when zoomed in. For example, near the ocean or on its shore, waves splashing and breaking up can be heard.
- Civilization 4 uses a 3D engine which allows zooming smoothly from world map levels down to individual squares. There's a set of overlays for world map levels.
- Wonder movies have returned after being absent in Civilization III.
- As game time passes and the player enters new eras, pictures of devices that measure the passage of time are shown. When the player leaves the Ancient era and enters the Classical era, a picture of a sundial appears. The player is shown a picture of an hourglass upon entering the medieval era, an armillary sphere upon entering the Renaissance, an analog clock upon entering the Industrial Age, a digital clock upon entering the Modern Era, and, in Beyond the Sword, an identical digital clock upon entering the future era.
- The Three Gorges Dam has replaced the Hoover Dam, which was a Wonder used in previous versions.
- Spaceship journeys to Alpha Centauri are always successful in games prior to the second expansion, Beyond the Sword, after which the chance of success once again varies depending on how complete the spacecraft is; it is possible, by fully constructing the spacecraft, to guarantee success.
- Civ IV is the first in the franchise not to feature SETI as a wonder.
Sid Meier's Civilization IV included some bonus content, released with mainly the purpose of showing modding capabilities:
- Earth – This is the world map of the game. 124x68 tiles big, it features just 9 ancient civilizations. It is based on the Robinson projection of the Earth in order to optimize its size. Later, an 18 civilizations version was released, and being reckoned "flawless", it won the first prize at GameFlood modding contest.
- Earth Ice Age – This map is set in the world during the last ice age (20,000 years before present). 11 randomly picked civilizations are contained in this map.
- Earth 1000 AD – 13 civilizations populate the world in this recreation of the Earth at the time of the Crusades.
- Greek World – To reenact the classical Mediterranean, a special map was made, based on Hecataeus' map of the world, as it was known by the Greeks. Extra detail is borrowed from other ancient sources such as Homer, Ptolemy, and Herodotus.
- Desert War – This scenario represents the Mediterranean theater of World War II. Axis and Allies have different cities as objectives. They can win the game by holding them for 10 turns.
- American Revolution – This scenario begins in 1775 AD. Player can side with American colonists or with the British Crown.
- Rhye's and Fall of Civilization – This scenario offers the "closest-to-reality" experience with much of the core settings of the game having been changed to ensure historical realism. Includes a dynamic rise of civilizations and other features like stability, plagues, congress and different Unique Historical Victories for each civilization. The player can decide to begin at the dawn of humanity (3000 BC) or at the beginning of the Middle-Ages (600 AD). It is currently one of the three user-made mods to be officially included with the game.
Civilization IV is much more open to modification than its predecessors. Game data and rules are stored in XML files, and a Software Development Kit was released in April 2006 to allow AI customization. Major parts of the interface, map generation, and scripted events are written entirely in Python and can be customized.
The World Builder allows a player to create a map from scratch or to use an in-game situation as a starting point for a new scenario. The player can modify the map by placing and modifying rivers, landmasses, mountains, resources, units and cities. For example, it is possible to adjust a city's population or culture. Additionally, each civilization's technological progress as well as its diplomatic and military ties to other civilizations can be edited. The world builder can also be used during the middle of a campaign to change anything from names of cities to giving yourself more units making it a quite useful in game cheat device. The World Builder for Civilization IV is in-game, in contrast to previous Civilization games where the Map Editor was an external application.
More game attributes are stored in XML files, which must be edited with an external text editor or application. Barry Caudill, a senior producer at Firaxis Games, said in September: "Editing these files will allow players to tweak simple game rules and change or add content. For instance, they can add new unit or building types, change the cost of wonders, or add new civilizations. Players can also change the sounds played at certain times or edit the play list for your soundtrack."
At the current time[when?] the XML processing in Windows is permissive of errors, whereas the Mac OS X version is not. As a result, some XML files which will work on the Windows version of the game may need correcting before they function correctly on the Macintosh version.
The game uses boost.python to allow the Python access to many parts of the game (including the style and content of all interface screens). Python can also be used to modify random map generation and to add complex scripted events. The version of Python present in the Windows version of the game differs from the version in Mac OS X up to and including version 10.4.7, and as a result, while most Python files for the Windows version will work on the Macintosh version, not all will. The reverse is also true.
The Civilization IV software development kit was released on April 13, 2006, to coincide with the release of the v1.61 patch. The kit allows players to view, modify, or completely re-write the game's DLL source code, enabling the modification of the game's AI and other integral parts of the game.
As of the first official patch for the Macintosh version (v1.61 Revision A), there is no SDK for the Macintosh version of the game. In fact the Macintosh version lacks the separate library of game related code which the PC version uses, but instead includes the code compiled into the main executable. There is no indication yet of whether this will change in a future patch.
The release of Civilization IV reportedly included some technical, production and shipping problems. The most common packaging errors have been French and German technology charts in English-language boxes and the erroneous packing of two of the same CD-ROM, rendering the game unplayable. 2K Games replaced such shipments. Other copies have mislabeled disks; since this does not affect gameplay, users are asked to just use the right CD-ROM when applicable. There have also been some cases in which the game manual has pages situated in the wrong place (e.g.: page one is the very last page of the manual). There are also many typographical errors in the Dutch manual.
Civilization IV is available for Windows (PC) and Mac OS X. The Mac OS X version is published by Aspyr and was released in June 2006. A Mac digital version was released January 2010 on gameagent.com. Though it lacks some of the customization features which were added to the PC version in v1.61, it is otherwise identical to v.1.61 of the PC version. The game was released as a Universal binary, running natively on both PPC- and x86-based Macintoshes.
Civilization IV and its expansions are also available via Steam and Turner Broadcasting System's GameTap subscription service. Multiplayer games involving both game platforms work, but require the use of one of the multiplayer options other than "Internet Play" due to the incompatible formats employed.
A re-make of the original (1994) Sid Meier's Colonization built with Civilization IV's game engine, Civilization IV: Colonization, was released for Mac and PC. It is a standalone game, playable without the original Civilization IV.
Recently Oasys Mobile published various arcade games under the brand name of Sid Meier's Civilization IV like Civilization IV: War of Two Cities, a catapult game, and Civilization IV: Defenders of the Gates, which is a tower-defense game.
Two expansion packs have been published for Civilization IV. The first one, Civilization IV: Warlords, was released in the United States on July 24, 2006, and in Europe two days later, on July 26, 2006.
The second expansion pack, Civilization IV: Beyond the Sword, was released on July 18, 2007, in the United States and on July 20, 2007, in Europe. The expansion focuses on adding content to the in-game time periods following the invention of gunpowder, and includes more general content such as 11 new scenarios, 10 new civilizations, and 16 new leaders. It also expands the technology tree.
|PC Gamer (US)||94%|
Civilization IV was exceptionally well received by video game critics, with an aggregated review score of 94 on Metacritic. The game was generally praised for its depth in strategy and for competent AI opponents, with several critics calling the game "addictive" and "infinitely replayable". At the same time, many critics appreciated the more streamlined and intuitive interface as well as the visual and sound design, describing them as more welcoming of newcomers to the series.
Other reviews included:
- ActionTrip 93/100 (5 November 2005)
- Chicago Tribune 4/4 stars
- Computer Gaming World A (5 November 2005)
- Pelit (Finnish): 97/100
- The Times 5/5 stars
Civilization IV won multiple awards at various events and gaming websites. IGN chose the game as the PC Game of the Year in 2005 over F.E.A.R. and Guild Wars, and also as the Best Strategy Game (both overall and on PC) and Best Online Game of 2005 on PC. In 2007, IGN also ranked it at the second place on the list of top 25 PC games of all time. GameSpot awarded the game Best PC Game and Best Strategy Game of 2005, and nominated it for Game of the Year. GameSpy named the game Game of the Year, PC Game of the Year, and Best Turn-Based Strategy Game of 2005.
At the ninth Annual Interactive Achievement Awards, Civilization IV won Strategy Game of the Year and was nominated for Overall Game of the Year (lost to God of War) and Computer Game of the Year (lost to Battlefield 2). At the 2010 Grammy Awards, the Civ IV theme, Baba Yetu, won in the Best Instrumental Arrangement Accompanying Vocalist category, as the first Grammy Award nomination and win for any video game theme.
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- Official website
- Official website (Macintosh version)
- Sid Meier's Civilization IV at MobyGames
- Civilization IV at the Open Directory Project
- Civilization series wiki