Civilization V is a turn-based strategy game, where each player represents the leader of a certain nation or ethnic group ("civilization") and must guide its growth over the course of thousands of years. It starts with the founding of a small settlement and ends after achieving one of the victory conditions—or surviving until the number of game turns end, at which point the highest-scoring civilization, based on several factors, such as population, land, technological advancement, and cultural development, is declared the winner.
During their turn, the player must manage units representing civilian and military forces: directing units to explore the world, found new cities, go into battle to take over other civilizations, control production in their cities to produce new units and buildings, improve land, handle diplomacy with other civilizations in the game, and finally direct the civilization's growth in technology, culture, food supply, and economics. Victory conditions can include taking over the entire world by force, convincing the other civilizations through diplomacy to acknowledge the player as a leader, becoming influential with all civilizations through tourism, or winning the space race to build a colony spaceship to reach a nearby planet, or winning from being the most powerful civilization on the globe after a set number of turns.
The artificial intelligence (AI) in Civilization V is designed to operate on four levels: the tactical AI controls individual units; the operational AI oversees the entire war front; the strategic AI manages the entire empire; and the grand strategic AI sets long-term goals and determines how to win the game. The four levels of AI complement each other to allow for complex and fluid AI behaviours, which will differ from game to game. Each of the AI-controlled leaders has a unique personality, determined by a combination of 'flavors' on a ten-point scale; however, the values may differ slightly in each game. There are 26 flavors, grouped into categories including growth, expansion, wide strategy, military preferences, recon, naval recon, naval growth, and development preferences.
As in previous versions, cities remain the central pillar of Civilization gameplay. A city can be founded on a desired location by a settler unit, produced in the same way as military units, and the city will grow in population, produce units and buildings, and generate research, wealth and culture. The city will also expand its borders one or more tiles at a time, which is critical in claiming territory and resources. The expansion process is automated and directed towards the city's needs, but tiles can be bought with gold.
Siege warfare has been revamped. Whereas cities in previous Civ games relied entirely on garrisoned units for defense, cities in Civ V now defend themselves, and can attack invading units with a ranged attack expanding two tiles outward. Cities have hit points that, if taken down to zero, will signal the city's defeat to invading forces; surviving an attack allows a city to recover a fraction (approximately 15%) of its hit points automatically each turn. In addition, any melee unit loses hit points upon attacking a city, dependent upon the strength of the city and unit. Hit points can be increased by garrisoning a unit in the city or building defensive structures (e.g. walls).
Captured cities can be annexed, razed, or transformed into a puppet state, each option having distinct advantages and disadvantages; for example, puppet states will provide resources, have lower unhappiness, and not increase the cost of cultural policies, but has reduced science and culture yields and cannot be directly controlled, being controlled by the A.I. instead.
In this iteration of the series, tactical gameplay in combat is encouraged in place of overwhelming numerical force, with the introduction of new gameplay mechanisms. Most significantly, the square grid of the world map has been replaced with a hexagonal grid, a feature inspired by the 1994 game Panzer General, according to lead designer Jon Shafer. In addition, each hexagonal tile, including city tiles, can accommodate only one military unit and one civilian unit or great person at a time, forcing armies to spread out over large areas rather than being stacked onto a single tile. This has the effect of moving most large battles outside of the cities, and forces increased realism in sieges, which are now most effective when surrounding the city tile because of bonuses from flanking.
Increased movement points, simpler transportation over water (embarkment instead of unit transport with water vessels), ranged attacks, and swapping of adjacent units allows for more precise maneuvering of units. There is also a balance between ranged and melee units. Ranged units can attack melee units without retribution, but melee units will normally destroy ranged units.
In an effort to make individual units more valuable to the player (compared to previous games in the series), they take longer to produce, and gain experience from defeating enemy units. At set levels this experience can be redeemed for promotions, which provide various bonuses for increasing their effectiveness, or to substantially heal themselves. In a further departure from previous games, units are no longer always destroyed if defeated in combat, taking partial damage, which can be healed at various rates depending on their type, location, and promotions earned. However, healthy units can still be completely destroyed in a single engagement if the opposing unit is much stronger.
Special "Great Person" units are still present in the game, providing special bonuses to the civilization that births them, with each named after a historic figure such as Albert Einstein or Leonardo da Vinci. Great people come in several varieties, and those available in the base game can be consumed to produce one of three effects: start a golden age, build a unique terrain improvement, or perform a unique special ability. For example, a Great General can create a 'Citadel' (a strong fort with the ability to inflict damage on nearby enemy units), or increase the combat strength of nearby friendly units (this is the only ability that does not require the consumption of the unit). With the exception of Great Prophets in the expansion sets, capturing a Great Person destroys him or her. Many Great People in the game have bonuses linked to the special ability of the Civilization; for example, one of Mongolia's special abilities is to increase the movement rate of great generals from 2 to 5 and rename them into "Khans".
The technology trading that occurred in previous titles in the series has been removed in favor of joint technological ventures. Two civilizations at peace can form a research agreement, which for an initial investment of gold provides both a certain amount of science so long as they remain at peace. Prior to the 220.127.116.112 PC version of the game, research agreements provided both parties with a random unknown technology after a set number of turns of uninterrupted peaceful relations. It is possible for a civilization to sign a research agreement for the sole purpose of getting an enemy to spend money which could be used for other purposes; AI civilizations are programmed to sometimes use this tactic before declaring war. British actor W. Morgan Sheppard provides the narration for the opening cinematics to the original game and its expansion packs, the quotations at the discovery of new technologies and the building of landmarks, and the introduction of the player's chosen civilization at the start of each new game.
This article uses material from the Wikipedia article Civilization V, https://en.wikipedia.org/wiki/Civilization_V, which is released under the Creative Commons Attribution-Share-Alike License 3.0, https://creativecommons.org/licenses/by-sa/3.0/.