Civilization IV (also known as Sid Meier's Civilization IV) is a 2005 4X turn-based strategy video game developed by Firaxis Games and published by 2K. It is the fourth installment of the Civilization series and was designed by Soren Johnson. It was released in North America, Europe, and Australia, between October 25 and November 4, 2005, and followed by Civilization V.
Civilization IV uses the 4X empire-building model for turn-based strategy gameplay, in which the player's main objective is to construct a civilization from limited initial resources. Most standard full-length games start the player with a settler unit and/or a city unit in 4000 BC. As with other games in the series, there are by default five objectives the player can pursue in order to finish the game: conquering all other civilizations; controlling a supermajority of the game world's land and population; building and sending the first sleeper ship to the Alpha Centauri star system; increasing the "Culture ratings" of at least three cities to "legendary" levels; or winning a "World Leader" popularity contest by the United Nations. If the time limit for the game is reached and none of the previous goals has been fulfilled by any players including game AI players, the civilization with the highest total game score is declared winner. A large departure from earlier Civilization games is a new graphics engine created from scratch, based on the Gamebryo engine by Numerical Design Limited (NDL).
The game has received critical acclaim and was hailed as an exemplary product of one of the leading video game producers in the turn-based strategy genre, and has been listed as one of the best video games of all time. Civilization IV sold over 3 million copies by 2008 and won multiple awards, including several Game of the Year awards. Its title song, "Baba Yetu", was the first piece of video game music to win a Grammy Award. Two major expansions were released, Civilization IV: Warlords and Civilization IV: Beyond the Sword, as well as the stand-alone expansion pack Civilization IV: Colonization, which were all combined in 2009 into one release edition titled Sid Meier's Civilization IV: The Complete Edition.
Gameplay Civilization IV follows some of the 4X model of turn-based strategy games, a genre in which players control an empire and "explore, expand, exploit, and exterminate", by having the player attempt to lead a modest group of people from a base with initially scarce resources into a successful empire or civilization.For sources that go into detail about each of the four Xs, see: ; ; The condition for winning the game is accomplished through one of the five ways: militarily defeating all other civilizations in the game world, controlling over two-thirds of the game world's land and population, building the first spaceship in the Space Age and sending it to Alpha Centauri, having the most dominant Culture ratings over other civilizations, or becoming "World Leader" through the United Nations votes. Additionally, there are multiple game scores for each civilization throughout the game based on the actions of each civilization and a number of factors, allowing for a win condition based on the total of these points if the game timer runs out. The game can be played in multiple modes: as a single player facing against one or more computer-controlled opponents, in hot seat mode, or through online multiplayer games.
As with other turn-based strategy video games, the player can customize the look and feel of their game world as well as the difficulty of any game AI players before the game starts. Each map space has a terrain type, such as plains, tundra, or desert, that affects the available resources players can extract from their environments and the movements of certain units through that terrain. The player is then given 34 civilizations to choose from, each with their own pros and cons, plus a leader avatar, an initial set of civilization technology, and any units unique to that civilization. When the game starts, however, it chooses random locations to place across a predefined square grid map. Like other strategy games, Civilization IV has a fog of war feature, in which unexplored territory remains darkened and territories without any units stationed on its designated square is shaded with darker colors.
Units and combat
Most units that the player can generate and use are military units, with certain attributes such as combat strength and movement rate particular to each military type. Each unit can gain experience through combat, which later translates into promotions that the player can use to assign military units new bonuses. Initially, most combat takes place on land, but further advancements in the game's technology tree can allow the player to build ships and planes with which to fight battles on sea and in the air. Any number of units can be stacked onto a single space and move as a group if so assigned, but the overall combat phase is resolved by one-on-one unit battles.
Combat is initiated when moving military units are moved onto the square occupied by an opposing force's military units and cities, and combat is then resolved with calculating statistics of each unit combined with some random chance. Defeated units are removed from the game (apart from workers and settlers, which are captured by the attacking force), and any attacking units that are able to defeat the last defending military unit on a space will move to occupy that space. If the space is occupied by a city the player may choose to occupy and capture the city as their own or raze it. Other than combat, military units can also be assigned to fortify a specific space, perform sentry duties, destroy enemy city improvements, or explore the game world.
Non-military units include settlers who are used to found cities, workers who are used to improve space and gather resources, spies who can perform counterintelligence and espionage, and religious missionaries who can be sent to convert different civilizations and cities. Also, with the Beyond the Sword expansion, new units are added such as executives, who can spread corporations to new cities. Throughout the game, players may also generate a special unit called a "Great Person". These are named after historical figures and can be used for one-time advantage boosts in various ways; examples include Great Engineers who increase overall production levels and Great Scientists who improve technology. Assigning inhabitants of cities to work as 'specialists' (scientists, engineers, artists, spies, merchants or priests), building certain wonders or discovering certain technologies can improve the rate at which Great People are generated. Great Generals are generated when a player's forces achieve a certain number of victories, and can be used either to give a small amount of extra experience to all units trained in a city, or a very high level of experience to one unit. However, like other units, Great People of all kinds can be attacked and killed before the players can use them.
Resources and buildings Once a city is founded, it will automatically begin extracting resources from surrounding spaces; the amount of spaces it can extract from is determined by the city's population size. The game automatically allocates the spaces a city uses and how its resources are maintained as the city grows, but the player is free to manage the city directly. This feature can be utilized to turn a part of the population into one of several specialized occupations; at the cost of having one less space from the city, these specialists increase gathering and production of the resources of their targeted specializations.
Each city can only produce one military unit or one building at a time; any additional units or buildings are placed into a queue. The rate of construction is determined by the amount of material collected from the surrounding spaces; players can also choose to speed production by sacrificing gold or population if they adopt the required governmental policy; called civics. The player can instead specialize the city towards gathering a particular resource instead of constructing additional units or buildings. Also, in order to produce some units or buildings, certain resources must be collected within the empire and connected to the empires trade network by roads or harbours (for example, horses are needed for mounted units, and iron for swords, while stone or marble increase production of certain Wonders.).
Buildings perform any number of different functions depending on building type; for example, early buildings such as granaries improve food storage to boost the city's growth and barracks produce better military units, while later buildings such as factories increase general production levels. There are also a number of unique buildings throughout the game. Most notable are World Wonders, which can be accessed through research nodes in the technology tree and construction through the worker unit. World Wonders provide advantages that are unique to each civilization, as they are limited to only one or two players.
Through buildings and specialists, each city also generates the "Culture" resource that contributes towards both the area upon which the city can influence for extracting resources and the overall civilization's cultural value. When two cities of different civilizations are adjacent to each other, the culture values of each city influences the space they can control; it is even possible that a city close to another civilization's city will join that civilization if their culture is strong enough. The high levels of culture gathering and attainment are also one of the default conditions that can be used to win the game.
Technology, government and religion
Once the first city has been founded, the player can select their first technology node from the game's technology tree to research, once the required number of research points have been accumulated, the technology is obtained. As with other types of technology trees, more advanced technology nodes require the research of other previous technology nodes. The player can also select a future technology and immediately place into the game queue any technology nodes between the current technology level and the specified technology node. Technology can also determine another win condition; several endgame technology nodes are required to develop a colony ship to reach Alpha Centauri.
Within the technology tree are technology nodes relating to government civics and state religions, each with their own pros and cons. The player has the option of selecting which set of government civics or state religions that the player wants their civilization to follow, but not all civics and religions can be encompassed.
Once the player has formally met another civilization, they can perform diplomacy at any time. For example, if the two civilizations are on friendly terms, the player can ask to trade units and/or technology for gold and vice versa, or request opening of national borders in order to freely explore in the other civilization's territories. The player can also use the diplomacy menu to request help in a war against a third civilization, or formally declare war on any civilization in which they engage diplomacy.