Sid Meier's Civilization IV
Developer(s)	Firaxis Games
Publisher(s)	2K Games
Designer(s)	Soren Johnson
Engine	Gamebryo
Platform(s)	Windows Macintosh (in development)
Release	U.S. & Canada: October 25 2005 Germany/Switzerland: October 26, 2005 Europe: November 4, 2005
Genre(s)	Turn-based strategy game
Mode(s)	Single player, mulitplayer

Sid Meier's Civilization IV (or Civ IV) is a turn-based strategy computer game, released between October 25 and November 4, 2005 in North America, Europe, and Australia. Developed by lead designer Soren Johnson under the direction of Meier and his studio Firaxis Games, it is the latest installment of the acclaimed Civilization series started by Sid Meier. A Macintosh version has been announced for a release in May 2006, along with a new expansion pack called Warlords, which is due to be released in July 2006.

Many aspects of Civilization IV are new to the series. These include:

• There are Great People that fall into five categories: artists, merchants, prophets, engineers and scientists. Each of these grants several bonus abilities. Among the Great People included are Xi Ling-Shi, Plato, Moses, Homer, William Shakespeare, Ramakrishna, Michelangelo, Isaac Newton, Zoroaster, Jalal al-Din Muhammad Rumi, Coco Chanel, Albert Einstein and Li Po. (See List of historical figures in Civilization IV for a full list of people and cultures used in Civ IV.)
• Instead of subtracting from a city's population upon completion, Settler and Worker units require the city to suspend its population growth, on the theory that all its new citizens are being funneled into the unit, until it contains enough people to depart. This makes Settlers significantly more difficult to build in small cities, and encourages players to build up their cities before expanding.
• The concept of city maintenance replaces corruption, which has been removed. Civilizations with a large number of small or ineffective cities will find their empire too expensive to maintain.
  • These two modifications together prevent a common strategy called Infinite City Sprawl (ICS), where numerous new cities are built as quickly as possible without regard for the consequential increase in city maintenance.
• One civilization's units cannot cross another civilization's territory unless the civilizations are at war or have agreed to an open borders treaty.
• Governments have been replaced with a more flexible civics model, where the player can set the amount of freedom the citizens have (slavery, free speech, etc.). There are five different categories in the new civics model (Government, Legal, Labor, Economy, and Religion), and five separate options within each category. This appears to be adapted from the Social Engineering section of Sid Meier's Alpha Centauri.
• AI civilizations no longer act as if they have knowledge of the entire map.
• The AI is more intelligent. They make full use of all options and have better long-term planning abilities.

• New diplomacy options include influencing other civilizations to stop warring or trading with other civilizations and asking them to change religions or civics. However, different trade options require different advancements to unlock, and some things may only be traded for certain other things (e.g., per turns deals must be compensated by another per turn deal).
• The reasoning behind diplomacy is now more transparent: the Diplomacy window now not only displays the other leaders' attitudes (friendly, pleased, cautious, annoyed, furious), but why they feel that way (e.g "-2: You refused to stop trading with our worst enemies!").
• The United Nations wonder allows passing global resolutions (e.g. the Nuclear Non-Proliferation Treaty) in addition to granting access to diplomatic victory. Unlike real-world resolutions, Civilization IV's resolutions are binding.

Units no longer have separate attack and defense values. Instead, they have a base strength that is increased or decreased depending on the situation. The unit's strength also impacts how much damage it can do. Prior to the 1.52 patch, the unit's damage was calculated using its current strength (which also acts as life/hitpoints and changes accordingly). After the patch, the damage is calculated from the base strength - this means that badly damaged modern units can still easily win battles against obsolete units. Instead of generic increases in rank, individual units gain specific types of combat experience, such as bonuses against specific types of enemies or abilities like faster movement in forests. In total, there are 41 different types of combat promotions. It is also now possible for players to examine "combat odds" before attacking, giving the player a good sense as to whether a given attack will succeed or not, factoring in all the various bonuses and penalties associated with terrain, unit capabilities, and so forth.

The 1.61 patch brought further changes, and now damaged units attack or defend with the average of their current and full strengths.

• The game features 32 types of resources, all of which are tradeable and require an improvement (such as a mine or an oil well) to be utilized. Some resources are required for certain units, buildings, or wonders; some may double the production speed of a certain wonder; and some act as luxuries like in Civ III, providing either happiness or health to all cities connected to them. There are also three types of culture goods provided by World Wonders, rather than resources, that can be traded: Hit Singles, Hit Movies and Hit Musicals.
• Cities on the same river or coastline are automatically connected for trading purposes.
• The player is no longer able to transfer all production from one project to another, but all production on a certain project will remain. For example, if the player is building a temple but decides to switch to a harbor, production on the harbor will have to start from scratch. However, the temple stays in the building queue and retains its 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 amount of Production points lost.

• Pollution, size restrictions, and similar aspects from earlier games are combined into one "City Health" system. Resources and improvements - such as wheat and hospitals - add health points, while population growth and industry decrease them. A negative total causes a food production penalty for the city. Fallout continues to exist in the case of a nuclear attack or meltdown.
• Similarly, cities no longer fall into tedious disorder. For each unhappiness point over the amount of happiness points, one citizen refuses to work.
• 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 resources are carried over rather than wasted.

• More emphasis has also been put on the soundtrack, which features Renaissance (Desprez, da Palestrina, etc.), Baroque (Bach), Classical (Mozart and Beethoven), Romantic (Brahms, Dvorak, Rimsky-Korsakov, and Saint-Saëns), Minimalism (John Adams), and self-composed (mainly by Jeff Briggs) music.
• The scale of music used in the game is enhanced from some of the previous versions. Each leader has a unique piece of music played during diplomacy (with the exception of Kublai Khan who shares his music with Genghis Khan). Many of the pieces are popular and familiar; for example, Roosevelt's music is the Marines' Hymn, and Napoleon's is a variant on the Marseillese. Some are renditions of famous pieces, such as Frederick's piece, which is a paraphrase of the fourth of the Goldberg Variations. 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.
• With each built improvement a sound related to it when it is accomplished is played. Ambient sounds can also be heard near different terrains. 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 are back and they, arguably, show the best graphics in the game.

The concept of separate religions is new to Civ4. In previous games, players could build temples and cathedrals, but the religion was just a generic feature of happiness and culture. There are now seven distinct religions in the game — Buddhism, Christianity, Confucianism, Hinduism, Islam, Judaism, and Taoism. In order to prevent anyone from being offended because of an issue related to their religion while playing, there are no bonuses or traits specific to any religion, except that each religion is tied to a specific technological advance, and the four later religions (Christianity, Confucianism, Islam, and Taoism) begin with a free missionary; however, this is more for game balance than anything else. If a player is the first to discover a certain religion on the tech tree, they can "found" the new religion; a city with no religion or the newest city in that civilization's empire becomes that religion's holy city.

As the game progresses, both the players' and the AI's religions will slowly spread by themselves, especially to cities that do not yet have formal religions. Players and the AI can also greatly accelerate the process through missionaries, monasteries, shrines, other buildings and units, and acts of diplomacy such as asking another nation to convert to one's religion. If a player controls the holy city of a religion, they are able to have line of sight in cities that share that religion, and can also build holy structures that inspire foreign citizens to send gold to that player's coffers by means of expending a Great Prophet in the holy city. Two civs with the same religion (ie. the player and an AI civ) will be more friendly to one another in trade and diplomacy; those with different religions will display varying degrees of hostility. These effects are amplified for civilizations controlling their religion's holy city.

The new civics model of government also has a strong effect on religion: players can found a state religion, declare religious freedom, or take other actions that have profound impacts on the religious lives of their subjects. If a civilization has no declared religion, they are exempt from diplomatic advantages/disadvantages through religion.

• Eight of the eighteen civilizations have two leaders. Each leader offers bonuses based on what conditions were exceptional during the historical reign of that leader, and each leader acts as differently as if they were a separate civilization and have distinct personalities.
• Several historic figures not used in previous Civ games are AI leaders in Civ4, including: Asoka, Cyrus II, Franklin D. Roosevelt, George Washington, Hatshepsut, Mansa Musa, Kublai Khan, Peter the Great, Qin Shi Huang, Saladin (though Saladin was a hidden leader in Civ 2), and Queen Victoria.

Civilization IV Civilizations and Leaders Chart

As in prior versions of Civilization, there are technologies for the civilizations to discover. But there are many new changes.

• Unlike in Civilization 3, Civilization 4's six eras of technological advancement (Ancient, Classical, Medieval, Renaissance, Industrial, and Modern) are loosely defined, so players are not required to discover all major technologies in one era to advance to the next. In the custom game menu however, it lists a seventh era of technological advancement, the Future, which starts every player with all technologies researched.
• There are a total of 86 technologies in the game, up from 81 in Civilization III.
• Technology development is more flexible: certain technologies can be discovered in more than just one way.
• The game has a very useful tech tree. This can be accessed by pressing F6 on the keyboard. The tech tree displays all the techs in the game and their relations with one another. It is possible to select even unavailable techs for research. This will cause all the prerequisite techs to be researched in order. If multiple paths lead to the target tech, the civilization will pick the shortest.
• The final tech or group of techs, as in previous versions, are called "Future Tech", followed by a number. Instead of simply adding on to the final score, however, each city receives a happiness and health bonus for each future tech discovered.
• In single-player games, the discovery of each tech during the game is accompanied by a famous quote from history which is voiced by Leonard Nimoy of Star Trek fame. Some of the quotes mentioned have come from (but not limited to) Buddha, Charles Darwin, Brillat-Savarin, Steve Wozniak, Henry Ford and the Bible.

• In Civilization II and III, after the computer worked out the player's final score, a title was given to the player, such as "Lion-Hearted," and "the Great." In Civilization IV, instead of a title, 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 Civilization I.

The game abandons Civilization III's graded scale. In Civ3, a spectacular victory on Cheftain mode (the easiest available) would provide the player with a fairly bad score, and the best titles were only awarded to players attempting the hardest difficulties. Civ4, on the other hand, allows the player to obtain any score on any difficulty level.

Civilization 4 is much more open to modification than its already mod-friendly prequels. Game data and rules are stored in XML files, a Software Development Kit was released in April 2006 to allow AI customization and, finally, major parts of interface, map generation, scripted events, etc are written entirely in Python.

Four levels of modification are possible:

The map editor, called World Builder, is accessible within the main GUI. It allows a player to create a map from scratch or to take any in-game situation as a jumping-off point for a new scenario. Terrain can be modified; resources, improvements, and military units added or removed; and cities built, erased, or altered. A bitmap importer allows the use of satellite data, and of other real-world (and imaginary) terrain maps.

The player can also choose what technologies are being researched, and the status of diplomatic and military ties.

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 [1] 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. NOTE: You can have custom soundtracks simply by adding music to the custom folder. You only need to edit the XML in order to assign certain pieces to specific eras or remove certain pieces."

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 highly-anticipated Software Development Kit was released on April 13 2006 to co-incide 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. [2]

The release of Civilization IV has not gone smoothly. Technical, production and shipping problems have marred its product cycle.

• 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 utility program was created to fix the memory usage problems. It was made redundant with v1.52.
• A major patch (v1.61) was released on 13 April, 2006. [3]. The patch made a number of gameplay tweaks, fixes and additions, including five new scenarios and three new map scripts. The patch also added support for the Pitboss turn-based server application. As before, the 45.7MB patch can be downloaded using the game's in-built updating utility, or from a variety of mirrors. [4]
• The most common packaging errors have been French and German technology charts in English-language boxes [5] and the erroneous packing of two of the same CD-ROM, rendering the game unusable. [6]. 2K games has been replacing such shipments for free. Other copies have mislabeled disks; since this does not affect gameplay, users are asked to just use the right CD-ROM when applicable [7]. 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.
• Civ IV uses SafeDisc 4, which refuses to acknowledge legitimate game copies if certain programs associated with unauthorized copying are installed. Unofficial work-arounds to SafeDisc exist.
• Many players have had experienced difficulty in multiplayer gameplay. When they attempt to join a game, their connection is refused by a fellow player's router or firewall, thus inhibiting gameplay. This problem is quite widespread in the Civ IV multiplayer community, and those players with routers or firewalls which reject other computers have been labeled as "bad peers." The problem is partially correctable by forwarding a series of ports on one's router or firewall [8] (this method has not consistently solved the problem for some users), and can be eliminated entirely by demilitarizing the router or firewall.

Despite all of these problems, many newer computers run Civilization IV quite smoothly.

• 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 incompatability of certain mods downloaded by users.

• IGN 9.4/10 Editors' Choice Award [9]
• GameSpot 9.4/10 Editors' Choice Award [10]
• Eurogamer 9/10 [11]
• GameSpy 5/5 [12]
• Computer Gaming World 90/100 (5 November 2005) [13]
• ActionTrip 93/100 (5 November 2005) [14]
• The Bovine Conspiracy 10/10 (3 November 2005) [15]
• Newspaper: The Times 5/5 stars [16]
• Newspaper: Chicago Tribune 4/4 stars [17]
• Magazine: PC Gamer UK 92%
• Magazine: PC Gamer 94%
• Magazine: PC Powerplay (German): 91%
• Magazine: PC ZONE (UK): 92%
• Magazine: Giochi per il mio Computer (Italian): 9/10
• Magazine: SuperPlay (Swedish) 10/10
• Magazine: PC Powerplay (Australian) : 10/10
• Magazine: Pelit (Finnish) : 97/100
• Magazine: Hyper (Australian) : 96%
• Magazine: Atomic MPC (Australian) : 10/10
• Magazine: Quantaz (Canadian) : 99%
• Television: X-Play 5/5

• IGN: PC Game of the Year 2005, Best Strategy Game 2005, Best Online Game 2005
• GameSpy: PC Game of the Year 2005, Best Turn-Based Strategy Game 2005, Game of the Year 2005
• GameSpot: Best Strategy Game 2005, Best PC Game 2005
• Time Magazine: Top Pick (E3 2005)
• Scripps Howard News Service: Game of the Year 2005
• For other awards click here.

• Sid Meier narrates the tutorial.
• Much of the game is voiced by Leonard Nimoy, famous for playing the role of Spock from Star Trek.
• In the cultural victory cutscene, the Colossus' face appears to be a composite of Sid Meier.
• Like in many other games, the manual goes into production before the developers have finished the game, and there are several notable errors:
  • All the results of all the games that have been played, regardless of victory or score, are listed in the "Hall of Fame" (despite what the manual says: If your victory is spectacular enough, your exploits might be recorded on the Civilization IV Hall of Fame screen)
  • In Civilization IV, corruption in cities was removed. However, in some manuals, corruption and how to reduce its effects is mentioned.
• The Three Gorges Dam bears a striking resemblance to the Hoover Dam.
• Elvis Presley has had some form of appearance in every Civilization title so far: in Civilization IV, the clothes of the Great Artist units, from the Industrial to the Modern Ages, and the "Rock and Roll" wonder are tributes to him.
• Spaceship journeys to Alpha Centauri are always successful.
• In the video for the Space Victory, the figure that jumps down resembles CEO Nwabudike Morgan from Sid Meier's Alpha Centauri.
• The name of the title song played at the start of the game is Baba Yetu. The title is "Our Father" in Swahili, and the song itself is a rendition of the Christian Lord's Prayer. It is performed by Talisman A Cappella and was composed by Christopher Tin. (lyrics and more information, sample)
• In the popup which tells the player that they have reached the Modern Age, there is a digital watch with the brand name Soren. This is a reference to Soren Johnson, the lead designer and AI programmer for the game.
• The Firaxis logo is the artwork on the sails of workboats.
• During the movie for the Broadway wonder, the cars are driving on the wrong side of the road.
• In a reference to a famous Al Gore quote, the former Vice President's face is featured in the graphic for The Internet Project.

• Civilization IV Official Strategy Guide. BradyGames. October 25, 2005. ISBN 0-744-00580-9. {{cite book}}: Check date values in: |date= (help)
• The sites listed below.

• Official site
• Developer's site
• Promotional Site
• Civ IV Comparisons

• CivFanatics
• Apolyton
• Planet Civilization
• 1BigCommunity

• civ.org.pl's Civilization IV information page
• CivGuide.com Strategy and more for Civ IV
• Civilization 4 Wiki
• Civilized Online Gaming Community
• Civilization IV in GameSpot
• Civilization IV at IGN
• Civilization IV discussion at 1BC
• Civilization IV Pre-release Guide with screenshots
• Extensive Pre-release Information at Noitazilivic
• Planet Civilization (Gamespy Network)