Sid Meier's Civilization IV (Civilization 4 or Civ4) is a turn-based strategy 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. The game's first expansion, Warlords, was released on July 24, 2006 in the United States and July 28, 2006 in the European Union. A second expansion, Beyond the Sword, was released worldwide between July 18 and July 30, 2007. As of March 26, 2008, Civilization IV has sold 3 million copies according to Take-Two Interactive.
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 the majority of the world's land and population, being the first to land a colonizing ship on Alpha Centauri, 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.
Civilization IV was released in English, German, French, Spanish, Italian, Japanese, and Chinese.
Diplomacy in Civilization
generally involves the trading of goods. Specific technologies are required to trade different commodities (for instance, one must know the secret of paper
to trade world maps
). Players may trade technologies, resources (including luxuries such as wine), maps (to reveal information about the rest of the world) and gold
. Advanced diplomacy options include the creation of trade embargoes
, the promise of military aid, and the adoption of particular civics and/or a religion
. Finally, the United Nations
wonder allows the passing of global resolutions
(e.g. the Nuclear Non-Proliferation Treaty
) in addition to granting access to the diplomatic victory. Unlike real-world resolutions, Civilization IV
resolutions are binding.
The reasoning behind diplomacy is more transparent when compared to Civilization III (Civ3): the Diplomacy window now not only displays the other leader's disposition towards the player (from friendly to furious), but why they feel that way (e.g "-2: You refused to stop trading with our worst enemies!"). When a leader is sympathetic towards another civilization, they are more likely to accept deals without unfair bargaining.
Instead of receiving generic increases in rank as in Civ3, the player is allowed to "promote" Civilization IV units with specific upgrades that provide bonuses in certain situations (+25% city defense, +25% vs. melee units, etc). There are 41 different types of combat promotions. It is also now possible for players to examine "combat odds" before attacking, giving the player an idea as to whether a given attack will succeed or not.
Units no longer have separate attack and defense values; instead, its health points are also its attack value. Prior to the 1.52 patch, a damaged unit had its combat strength likewise reduced; after the patch, flat base strength was used, allowing damaged units to still fight at full strength. After the 1.61 patch, damaged units fight with the average of their current and full strengths.
Production and trade
The game features 32 types of resources which require a terrain improvement (such as a farm or an oil well) to be used or traded. Resources enable construction (a knight
unit cannot be built without horses
), double the speed of construction (the Pyramids
are built twice as fast with stone
available) or simply add happiness or healthiness to all cities. To trade goods or to send them to other cities within one's border, they must have some form of connection between the goods and the city. In the later game, this connection can be through ocean tiles, but in the early game, it is limited to roads and rivers. Cities on the same river or same coastline (with the sailing
technology) are automatically connected for trading purposes.
Unlike in Civ3
, the player is no longer able to transfer all production from one project to another, but all production on an already-begun project will remain. For example, if the player is building a temple
but decides to switch to a harbor
, production on the harbor will start from scratch, but the temple will stay in the building queue and retain all previous progress, aside from some decay over time. As an ancillary rule, if one culture is building a World Wonder but another empire completes it first, the losing culture is compensated with gold proportional to the number of production points lost in the failed attempt to build the wonder.
Trade can be conducted with any civilization that the player has made contact with. AI Civ leaders tend to view resources in two groups. There are key resources such as stone, iron, uranium, and the likes that assist in weapon and building production, and all other resources, such as incense and spices, which are helpful to a Civilization but not necessary for unit production. The AI will typically not trade key resources away unless another key resource is being given. Thus all key resources are considered of equal value to the computer. Similarly all other resources that do not affect units and building are considered equal as well. This can lead to exploitation by using a less valuable Key resource to obtain a high demand one. For instance ivory (elephants) can be traded equally for uranium and the AI will gladly oblige if they are on fair terms with the player. Trading for a single instance of a resource gives you all the benefits of it.
The concept of religion
is new to Civilization IV
, where in previous games players built generic temples and cathedrals to contribute to happiness and culture. There are now seven distinct religions in the game: Buddhism
. Each religion is associated with a specific technology on the tech tree; the first civilization that gains the technology founds the religion. The four later religions (Christianity, Confucianism, Islam, and Taoism) begin with a free Missionary
unit for reasons of game balance; missionaries can later be trained only at a city that has constructed an associated monastery
. Other than this, there are no special traits or bonuses associated with any particular religion in order to avoid controversy.
Religion factors into a number of existing game mechanics. Civilizations that share a common state religion will find themselves more agreeable in their diplomatic dealings; conversely, civilizations with differing state religions will not be as close diplomatically. The religion's founder may also receive an economic benefit: if that civilization expends a Great Prophet at their religion's holy (founding) city, they will construct that religion's most sacred building, and it will generate 1 gold per turn for every other city that hosts said religion. Once a religion has spread to a city, there is no way to remove it from said city. Finally, if a civilization has a state religion and owns that religion's holy city, they will receive 'line-of-sight' (fog of war is lifted) in every other city hosting that religion.
The new civics model of government also has a strong effect on religion. Players can found a state religion, declare religious freedom, restrict non-state religious adoption, or take other actions that have profound impacts on the religious lives of their subjects. These civics can provide a great incentive to spread a state religion throughout one's empire, as the best bonuses will only be applied to cities in which the religion is present.
Civilizations and leaders
Each of the eighteen civilizations has at least one leader, and eight have two leaders. Each leader has two 'personality traits' which offer bonuses to various game mechanics, as well as a distinct personality and behavior. Several historic figures not used in previous Civilization games, but included in Civ IV
, Cyrus II
, Franklin D. Roosevelt
, George Washington
, Mansa Musa
, Kublai Khan
, Peter the Great
, Qin Shi Huang
(though Saladin was a hidden leader in Civilization II
), and Queen Victoria
. Some art assets also existed in the game files for a Sumerian
civilization led by Gilgamesh
and they were used by the modding
community to introduce the Sumerians into the game. Other unfinished art included leader head artwork for Pericles
, and Menes
. Gilgamesh, Pericles and Augustus were officially added in the expansion packs later.
All civilizations have some element of uniqueness and all leaders have certain traits based on their achievements in life. All civilizations also have a unique unit, which replaces a standard unit (such as Persian Immortals replacing Chariots). Below is a summary of the unique features of each civilization.
| Short Description
|| Starting Advances
|| Unique Unit
|| Leader Traits
|| Favorite Civic
|| First City |
||Navy SEAL (replaces Marine)
|| George Washington
|| Financial, Organized
|| Industrious, Organized |
|| Arabian Empire
|| Mysticism, The Wheel
|| Camel Archer (replaces Knight)
|| Philosophical, Spiritual
|| Mecca |
|| Aztec Empire
|| Mysticism, Hunting
|| Jaguar (replaces Swordsman)
|| Aggressive, Spiritual
|| Police State
|| Tenochtitlan |
||Cho-Ko-Nu (replaces Crossbow)
|| Mao Zedong
|| Philosophical, Organized
|| State Property
| Qin Shi Huang
|| Industrious, Financial
|| Police State |
|| Egyptian Empire
|| Agriculture, The Wheel
|| War Chariot (replaces Chariot)
|| Spiritual, Creative
|| Hereditary Rule
|| Thebes |
||Redcoat (replaces Rifleman)
|| Expansive, Financial
|| Philosophical, Financial
|| Free Religion |
||Agriculture, The Wheel
||Musketeer (replaces Musketman)
|| Louis XIV
|| Creative, Industrious
|| Hereditary Rule
|| Aggressive, Industrious
|| Representation |
||Panzer (replaces Tank)
|| Creative, Philosophical
|| Universal Suffrage
|| Expansive, Industrious
|| Representation |
|| Greek Empire
|| Fishing, Hunting
|| Phalanx (replaces Spearman)
|| Aggressive, Philosophical
|| Hereditary Rule
|| Athens |
|| Inca Empire
|| Agriculture, Mysticism
|| Quechua (replaces Warrior)
|| Huayna Capac
|| Aggressive, Financial
|| Hereditary Rule
|| Cuzco |
||Fast Worker (replaces Worker)
|| Industrious, Spiritual
|| Organized, Spiritual |
|| Japanese Empire
|| Fishing, The Wheel
|| Samurai (replaces Maceman)
|| Aggressive, Organized
|| Kyoto |
|| Malinese Empire
|| Mining, The Wheel
|| Skirmisher (replaces Archer)
|| Mansa Musa
|| Financial, Spiritual
|| Free Market
|| Timbuktu |
||Hunting, The Wheel
||Keshik (replaces Horse Archer)
|| Genghis Khan
|| Aggressive, Expansive
|| Police State
| Kublai Khan
|| Aggressive, Creative
|| Hereditary Rule |
|| Persian Empire
|| Agriculture, Hunting
|| Immortals (replaces Chariot)
|| Expansive, Creative
|| Persepolis |
|| Roman Empire
|| Fishing, Mining
|| Praetorian (replaces Swordsman)
|| Julius Caesar
|| Organized, Expansive
|| Rome |
||Cossack (replaces Cavalry)
|| Creative, Financial
|| Hereditary Rule
|| Expansive, Philosophical
|| Police State |
|| Spanish Empire
|| Fishing, Mysticism
|| Conquistador (replaces Knight)
|| Expansive, Spiritual
|| Police State
|| Madrid |
As in prior versions of Civilization, a set of technologies are arranged in a tech tree. A total of 86 are included in the game, up from 81 in Civilization III. Technologies have many uses; they can be used for trade, for the construction of new terrain improvements, units, buildings and wonders, to reveal new resources, for the founding of new religions, or for the development of new forms of government. To discover a new technology, it is first necessary to discover the prerequisite technologies (for example, democracy can only be discovered after the printing press).
Unlike previous versions, Technology development is flexible: certain technologies can be discovered by following more than just one path, and others (all six starting technologies, for example hunting) are not linked to by any technology and must be found from scratch. The game's technology tree displays all the techs in the game and their relation with one another, and allows the player to queue any number of technologies for research. If multiple paths lead to the target technology, the AI will pick the shortest. The final technology in the game, as in previous versions, is called "Future Tech", followed by a number; each iteration of it imparts a happiness and health bonus to that nation's cities. In previous Civ games, Future tech gave a score bonus, but no gameplay advantages.
The discovery of each technology is announced by the game's narrator, Leonard Nimoy of Star Trek fame. In the single-player game, he reads off a famous quotation pertaining to the technology; the sources of the quotations range from the Buddha, Charles Darwin and the Bible to Lonnie Donegan, Steve Wozniak, Dan Quayle, and a monotonic "Beep. Beep. Beep." attributed to the Sputnik space probe. In multi-player games, Nimoy simply declares, "You have discovered [Name of Technology]."
The game features a number of World Wonders that bestow certain advantages (often specific to the city in which it is built, or to the general benefit of the civilization that built it). A few Wonders that existed in prior versions were removed or modified to reduce their significance. For example, in prior versions the Pyramids (granary in every city) and Michaelangelo's Chapel (cathedral in every city) could dramatically alter the balance of gameplay. Now most wonders offer percentage bonuses, such as a 10% increase in some value, along with the cultural impact of the wonder itself.
The wonders available in Civilization IV are as follows:
In Civilization IV
the leadership skills of players are compared to a subjective list of twenty of the best or worst leaders in history, similar to the list in the first Civilization
game. The score is based on a number of factors, including military growth and success, population size and attitude, technological advancement, turns taken to win, construction of wonders and economic growth.
The released version of the game abandoned Civilization III's graded scale. In Civ3, a spectacular victory on the easiest difficulty would provide the player with only a middling score, and the best titles were only awarded to players attempting the hardest difficulties. The original Civilization, as well as Civilization IV, on the other hand, allows the player to obtain any score on any difficulty level. As of the v1.61 patch, the grading system has returned to the curved-by-difficulty scale.
- Conquest Victory - achieved by the player who successfully eliminates all of their rivals.
- Domination Victory - awarded when a player uses military might and cunning negotiation tactics to conquer a certain (often large) percent of the world's population and a certain (also large) percent of the global land mass.
- Cultural Victory - awarded when a player has developed a culture so powerful that three of their cities have achieved legendary culture status.
- Space Race Victory - achieved when a player completes all of the components necessary to send colonists off into space to found a new colony on Alpha Centauri and is the first to have their ship arrive there.
- Diplomatic Victory - awarded to the diplomatically gifted player who, after being elected UN Secretary General, is elected to a diplomatic victory by the players.
- Time Victory - achieved by the player who can do whatever it takes throughout all of human history to defeat enemies, expand their civs, win the hearts and minds of the people, and boasts the highest score at the end of the game, in 2050 AD. A time victory will only be enabled if any of the previous five victories are not achieved by 2050.
A multiplayer game of Civilization IV
tends to play very differently compared to a singleplayer game. The relatively predictable reactions and diplomatic relationships with AI controlled civilizations can no longer be relied upon. This has many ramifications for the success potential of various strategies employed in the game. Most notably, the game tends to become very focused on quick-hit warmongering tactics. Multiplayer games of Civilization IV
almost never reach the modern era. However, map types with larger amounts of water, and larger maps, can lead to a much longer game. Additionally, some custom scenarios, such as the Earth 18 scenario, have a cult following and may take many hours to complete and usually end in the modern era.
Generally, multiplayer games of "Civilization IV" are set up with a turn timer, which limits the time players can spend conducting their turns, and in simultaneous mode, which means that all players' turns are taken at the same time.
Since the initial release of Civilization IV, players have complained about bugs to online play. Specifically, games often go "out of sync," requiring certain players to rejoin the game. Sometimes after one player leaves a game, the game remains frozen permanently and cannot be continued. This "freezing" issue also frequently arises when players use the game's "Retire" function to quit. Additionally, multiplayer games often fall victim to "game crashers" who repeatedly pause games by hitting the Pause/Break button in-game.
Many aspects of Civilization IV
are new to the series. These include:
- Great People that fall into seven categories, the original great people are: artists, merchants, prophets, engineers and scientists; generals and spies are added in expansion packs. Great People can be used to create several different effects: they can join the city as a Specialist; provide a one-time bonus or unique building; contribute to the discovery of a new technology; or be used, two or more at a time, to trigger a Golden Age. Great People include Aristotle, Plato, Moses, Homer, William Shakespeare, Ramakrishna, Michelangelo, Leonardo Da Vinci, Isaac Newton, Zoroaster, Jalal al-Din Muhammad Rumi, Coco Chanel, Albert Einstein and Marie Curie. They can be born to any civilization.
- Great artists visually resemble famous people, such as Elvis Presley and William Shakespeare, even when they are not given those names. The Shakespeare-like one holds out a skull and says something sounding like "To be...or not...to be". This is a reference to Hamlet. The "create great work" button for the Great Artists is a picture of the Mona Lisa.
- The founding and spreading of religions and the adoption of a state religion (see above).
- Instead of subtracting from a city's population upon completion, Settler and Worker units cause the city to suspend its population growth by contributing its food production to the unit's total. Both units are relatively expensive—which, as implied by the in-game "Hints" feature, is to slow the pace of expansion by forcing players to spend time maturing their cities. (A Settler requires 100 points of food and/or production to create; in comparison, the Musketmen military unit requires only 80.)
- The concept of "city maintenance" replaces the concept of "corruption" (an unpopular feature of Civilization III). Instead of outlying cities losing some of their total production, each city in a CivIV empire pays a certain maintenance fee which rises when new cities are created. Thus, civilizations with a large number of small, underdeveloped or inefficient cities will find their empire too expensive to maintain.
- Governments have been replaced with a more flexible civics model with five different categories — Government, Legal, Labor, Economy, and Religion — and five separate civic options within each category. For example, the Labor category includes the civics tribalism, slavery, serfdom, caste system and emancipation. This appears to be adapted from the Social Engineering section of Sid Meier's Alpha Centauri.
- AI civilizations no longer act as if they start the game knowing what the map looks like. Instead, they make full use of all options and exhibit better long-term planning.
- Barbarians now form cities in unexplored or unwatched territories, often named after their tribe or culture (Hun, Visigoth, etc). These cities act and react like any other city: they send out worker units to improve terrain, can be captured or razed by military force, can be culture-flipped, and so on. However, they cannot be contacted via diplomacy. Barbarian cities do not produce settlers to expand with new cities, although new barbarian cities can crop up in unexplored territories, as mentioned above.
- The United Nations can pass resolutions, which appears to be adapted from Sid Meier's Alpha Centauri. Until the Beyond the Sword expansion pack, these resolutions were binding.
- Units now gain different promotions when they gain experience, enabling the player to specialize their units more. These promotions generally increase the unit's strength under certain conditions (in forests or jungles; against gunpowder-based units; when attacking cities) or provide other bonuses. Many units have inherent promotions, which help define their intended use (archers, for example, have an inherent promotion which increases their strength when defending cities or hills).
- Military units no longer have separate ratings for attack, defense and health, but instead a single strength rating. In general, when two units are set against each other, the one with the higher number wins; however, the aforementioned promotions may cause changes in the outcome. (Relatedly, a player may consult the probability of success before commissioning an attack.) Finally, as of the game's most recent patch, a damaged unit loses half that amount of combat strength. This revised combat system was largely in response to the "spearman-defeats-tank" problem that has plagued Civilization since its first iteration, wherein nuances of the game's mathematics would allow weak and obsolete units (generally controlled by the AI) to defeat stronger and more modernized forces (generally controlled by the player) on a far-more-regular basis than common sense would suggest possible.
- Pollution, size restrictions, and similar aspects from earlier games are combined into one "City Health" system. Resources and buildings — such as wheat and hospitals — add health points, while population growth and industry add unhealthiness points. Terrain near the city can have positive and negative effects on the health score; for example, forests and fresh water increase the health score, and detrimental terrain features such as jungles add unhealthiness. An unbalance in favor of sickness causes a food production penalty for the city. Fallout continues to exist in the case of a nuclear attack or meltdown.
- Some streamlining elements have been introduced, such as the ability to select and issue orders to multiple units at the same time. When population grows, a new technology is discovered, or a new unit/improvement is built, any excess food, research, or production is carried over rather than wasted (truncated).
- Greater emphasis has been placed on the overall map-view mode. Where, in previous Civilization games, a player was often forced to access the City Management screen, almost all of its functions have been integrated into (or made accessible via) the standard map view, as have many abilities (diplomacy, research topic selection, tax rate, etc) that were formerly the domain of the Advisor screens. New players often play without leaving the map view, only as players gain the ability and need to micromanage are the specialized screens utilized.
- See also: Music in Civilization IV
- More emphasis has also been put on the game's soundtrack, which features compositions of Medieval, Renaissance, Baroque, Classical, Romantic and Minimalist origin, and self-composed pieces (mainly by Jeff Briggs). The name of the title song played at the start of the game is "Baba Yetu". The title means "Our Father" in Swahili, and the song itself is a rendition of the Christian Lord's Prayer. It is performed by Stanford University's Talisman A Cappella and was composed by Christopher Tin. (lyrics and more information, sample)
- Each leader has a unique piece of music played during diplomacy (with the exception of Kublai Khan and Genghis Khan who share music). Many of the pieces are popular and familiar; for example, Roosevelt's music is the "Marines' Hymn", and Napoleon's is a variant on "La Marseillaise". Some are renditions of famous pieces of classical music, such as Frederick's piece, which is a paraphrase of the fourth of the Goldberg Variations, or Bismarck's, which is the opening theme of the second movement of Beethoven's Symphony No. 3. Others, such as Mao Zedong and Alexander the Great have music that has been modified from earlier games, such as Civilization III. Still others have entirely original scores.
- Narrative voice acting, previously heard in Sid Meier's Alpha Centauri but never used in a game with Civilization in its title, 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.
- 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 the same 3D engine (Gamebryo) used in Sid Meier's Pirates!, which allows players to zoom smoothly from world map levels down to features in individual cities.
- Wonder movies have returned after being absent in Civilization III.
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 terrain can be altered, and resources, military units and cities on the map can be added, removed or modified. Additionally, each civilization's technological progress as well as its diplomatic and military ties to other civilizations can be edited. 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 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 programming language
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.
Software development kit
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 as of yet no indication of whether this will change in a future patch.
The release of Civilization IV
reportedly included some technical, production and shipping problems.
- As originally shipped, the game functioned poorly on minimum-specification machines, and suffered from performance problems. It also conflicted with certain mainstream graphics cards. A user created a utility program to fix the memory usage problems. Version 1.52 patched these 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 placed in the wrong spot (e.g. page one is the very last page of the manual). There are also many typographical errors in the Dutch manual.
- Civilization IV uses SafeDisc 4, which refuses to acknowledge legitimate game copies if certain CD burning or "virtual drive" packages are installed.
- The v1.09 patch for Civilization IV was released on 23 November 2005. While it fixed some memory leak issues, the patch seemed to focus more on tweaks to buildings and units, while also creating some problems of its own.
- The v1.52 patch, released on 22 December 2005, was a major update that fixed several of the major performance headaches relating to numerous memory leaks and usage. v1.52 also added several new scenarios and maps, in addition to tweaking.
- On 13 April 2006, the v1.61 patch was released. Also a major update, it fixed several performance issues remaining from v1.09 and v1.52, including the stuttering Wonder movie problem. Several new additions were made to the game, including two new map scripts, new game options and new scenarios. Many gameplay tweaks were also made. Although the patch was considered a success for some users, others have reported various problems, including a loss of text and sound. These problems seem to be related to the incompatibility of certain mods downloaded by users.
- The v1.74 patch was released on 19 July 2007. It contains several bug fixes and some game play tweaks. After the patch, several people reported problems on discussion forums. The reported problems stemmed from the fact that the patch required a recent version of DirectX 9.0c, which was not included with the patch, and therefore had to be updated manually. Confusingly, DirectX 9.0c has updates that are not included in the redistributable download from Microsoft. These updates still report as DirectX 9.0c but include additional files required by the game.
is available for Windows
(PC) and Mac OS X
The Mac OS X version is published by Aspyr and was released in June 2006. 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. Mac OS X users may also, in addition to the cross-platform GameSpy service (although Revision B is required for GameSpy), use GameRanger to play multiplayer games.
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.
Recently Civilization IV also has moved into the mobile market with Civilization IV: War of Two Cities. Oasys Mobile will be publishing this game in the spring of 2008.
Changes from previous versions
- 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.
- Individual citizens in each city no longer have their own nationality, as they did in Civ III. Instead, the nationality breakdown of each city has changed to a cultural breakdown; foreign culture can also affect a city without the use of military conquest.
- Civ IV is the first in the franchise not to feature SETI as a wonder.
- * PC Game of the Year 2005
- * Best Strategy Game 2005
- * Best Online Game 2005
- * 2nd PC Game Of All Time
- * PC Game of the Year 2005
- * Best Turn-Based Strategy Game 2005
- * Game of the Year 2005
- * Best Strategy Game 2005
- * Best PC Game 2005