Here is an article from a gaming magazine published in 2013:
A Classic Revived:
Review of Sid Meier's Civilization 6
Published in June, 2013
+ Most flaws of Civ 5 are gone
+ Policy system allows different player styles
+ Small-area civilizations are favored, less emphasis on landgrabbing
+ Less micro-management
- Some classical civilizations, leaders, buildings and units of previous games have been left out
The best-selling TBS series ever is back. Since its debut 1991, a new version of Civilization has been released every five years, most of them followed by expansion packs. The game mechanics of Civ 1 were simple, but each new game added new features, and Civ 4: Beyond The Sword was about as complex as a strategy game could get. Civilization: Revolution and Civilization 5 simplified the game again. "Dumbed down" and "broken", said hardcore fans, and hoped for an expansion pack to re-add religions, spies, growing villages and other popular Civ 4 elements. Firaxis never made a full expansion pack to Civ 5. However, they provided many pieces of downloadable content: civilizations, leaders, units and scenarios. Though beautiful and well-balanced (the World War I scenario was a multiplayer hit) and costing more than 60 USD put together, they didn't really make the game different.
2K and Firaxis decided to move on to a new standalone game, simple at release, intended to be made more complex with later expansion packs and scenarios. And it has gone gold just two and a half years after the last Civ game. As DRM remains a hot issue, 2K Games has sought new ways to offer value for legal copies. The box version of Civilization VI includes printed reference cards, and a decorated USB stick. Users registered in Europe can enjoy a streamed soundtrack by Spotify, totalling 60 hours of playtime of folk, world, classical and jazz music in the public domain. The opening menu melody is a choir interpretation of Jean Sibelius' Finlandia, actually composed to illustrate the birth of a nation.
A streamlined impression
The interface has an ancient look of marble and bronze, retaining the hex tiles, and the white fog of unknown lands from Civ 5. Other visual improvements include the full motion camera view and the option to view diplomacy in full-screen, split-screen or text-only. Civ VI has re-invented the elevation system of Sid Meier's Alpha Centauri; each hex has a height multiple of 250 metres. High ground provides good view and a defense bonus. This makes the map look a lot more dramatic, though the Earth map is not fully realistic. But has it ever been?
Spain made it to the 15 included nations this time, probably due to the enormous gaming market in Hispanic countries. If you miss Persia, Babylon, Mongolia, or any African nation besides Egypt, the setup menu offers a Civilization Maker, where you can import a flag, and write a list of city names. As Europe tends to be overcrowded, Civ VI offers a new feature called Alternate Starting Locations. With these turned on, some Western nations might start out in their real-world colonial realms. France could begin their quest in Québec, and the Greek nation could be founded in Mesopotamia (not too strange, since Babylon was a core city in Alexander's empire). Through online registration, users get the Persian civilization as a bonus.
Unique units are no longer fixed to one civilization. Instead, when a civilization discovers a technology that gives access to a unique unit, they can grab it, if no rival civilization took it first (though they are rationed, so that there is at least one for each player). AI leaders prefer their traditional units, so Catherine of Russia usually goes for MiG fighters. Civilizations have no truly unique abilities. They start the game with two Habitats (out of Arctic, Maritime, Pastoral, Temperate, Hydraulic and Tropical) with appropriate starting locations, offering combat and production bonuses in relevant territories. While Egypt starts out as Pastoral and Hydraulic, England becomes Arctic and Maritime. This hampers expansion into unfamiliar climate zones, just as in real-world history.
In lieu of our old friend Montezuma, the Aztecs are now led by his uncle, Ahuitzotl. If you thought Montezuma was ruthless, watch out for this guy!
Up to Civ 4, the primary sources of scientific research were budget allocation, and technology trading, which could rapidly spread new technologies around the world. To much disappointment, Civ 5 scrapped both. In Civ VI, the most straightforward way to new technologies is "building" them in the production queue. Later, specialists take on more of the research burden. Tech trading is back, now delayed by a few turns. Civilian agreements allow import of peaceful science such as Arch-and-Vault or Germ Theory without opening the Diplomatic screen, while a strategic agreement includes dangerous knowledge such as Horse Tack and Indirect Fire. Be sure not to open a strategic agreement with a treacherous rival! For the first time in the series, the number of cities penalizes research, so far-flung empires are not superior.
Disciplined, instead of happy
There are two new main resources. With Currency discovered, a share of the national budget can be funneled into Private Funds, illustrated by a top-hat () icon. By city, they attract luxury resources and maintain specialists, which in turn earn Great Person points. The city's amount of Private Funds are visualized by shacks transforming into region-specific architecture. They can speed up construction, but they are sensitive, and vanish during starvation, disorder or foreign attack. This adds a dynamic similar to the Cottage Economy of Civ IV. As Merchants and Great Merchants (represented by explorers and industrialists) produce Private Funds, a new specialist called Bureaucrat, raking in government funds. Among the Great Bureaucrats are many names who have advanced society, such as Plato, Niccolò Machiavelli, Karl Marx, Wellington Koo and Eleanor Roosevelt. As in Civ V, Priests and Great Prophets are absent.
Another resource, known as Discipline, has largely replaced Happiness. Illustrated by a pair of balance scales () Discipline is created by military structures such as Walls and Listening Stations, by Guard specialists (who also spawn Great Generals), garrisoned units and fights against barbarians. A high tax rate drains Discipline. Surplus Discipline can be spent on unit promotions, and annexions of foreign cities. There is no direct equivalent of War Weariness, but the supply, upgrade and promotion costs rise in foreign territory, making offensive war costly.
Apparently, a small, peaceful civilization needs little Discipline, while a leader bound for world conquest needs to build plenty of military buildings and employ lots of Guards in core cities, at the cost of civilian progress. When a city is deficient in Discipline, it falls into stagnation, unable to expand territory, train Settlers or grow more citizens. When Discipline is totally depleted, buildings might get damaged, but production never halts completely, as it used to do until Civ 3. This kind of crisis can be countered by devolving foreign-cultured cities into Dominions, which is similar to Vassalage in Civ 4, or Puppets in Civ 5.
Another use of Discipline, and the most important in the long run, is adoption of Policies. Civ 5 introduced the Social Policies, which could be adopted when the empire had collected enough Culture points. These are now known as Cultural Policies. Civ VI has a Discipline Policy tree and a Cultural Policy tree, both relating to each other. For instance, Warrior Class (a Discipline Policy), and Universal Suffrage (a Cultural Policy) cannot be active at the same time. Among Discipline Policies are Manorialism (extracts land tax), Single Party State (makes Guards much more efficient) and Strategic Bombing (damages enemy Discipline). The multitude of interlocking Policies offers a diversity of gameplay strategies, well compensating for the lack of civilization abilities. The AI leaders also have their clear profiles, with Isabella preferring Monarchy and Evangelism, and Lincoln going for Republic and Capitalism. If a city is distant from the capital, a portion of its produced culture diverges into a foreign national color (American for the English, etc), dragging down world domination.
Economic partnership or rivalry
City-states were introduced in Civ 5, giving huge food and culture bonuses to their allies. In Civ VI they act more like regular civilizations, able to build Wonders and enter agreements. Trade diplomacy used to be complex in Civ 4 and Civ 5, as each resource was traded in an individual agreement. Civ VI makes it simpler, introducing two kinds of trade agreements between civilizations, civilian and strategic. These can be one-sided. In a civilian trade agreement, civilizations automatically export all their surplus luxury resources for Private Funds. A strategic trade agreement also includes resources such as Iron and Oil. These are no longer essential for building any units, but they give significant production, mobility and combat bonuses, enough to be a deal-breaker at war.
Offices are a new tool of power. They represent social institutions in a city rather than physical buildings, such as a Consulate, a Mission or a Bank. Civilizations can create Offices in domestic and foreign cities, similar to religions and corporations in Civ 4, as a kind of "soft colonization", with the owner as the most favored part. Fans have already coined the term "Office Warfare".
Few units, but well-equipped and promoted
Much of the Civ 5 combat system remains, including embarkment and city hitpoints. Though the one-unit-per-tile rule was abandoned, units fight best when put in line formations, because of flanking bonuses. Archery and gun units are especially useful for this. As these units lost their Civ 5 ability to bombard, the bean-counting is reduced, to make room for more grand strategic thinking. A new Equipment system works parallel to promotions; units can be enhanced by Grenades, Radar and other supporting equipment (not visible in graphics, though) making up for the short list of units, where the Riflemen upgrade directly to Mechanized Infantry. As siege units and aircraft still bombard, targeted units are displaced to another tile before getting annihilated; though they lose equipment. A new system of visibility classes makes enemy units' promotions and equipment unknown, unless friendly units have Spyglass equipment, or Field Intel unit promotions.
Terrain improvements are now called Structures. They require much investment, but eventually allow great productivity on a small land area, and even yielding score. Solar Plants can make use of Deserts.
Civ 6 ends in 2025. Ironically, as this is the latest game in a series that began 22 years ago, the science-fiction part has been toned down. The classical Alpha Centauri victory has been demoted to a Mars Colony project, which feels more realistic anyway. The absence of Giant Death Robots is no great loss. There are no more units than Civ 4 or Civ 5, but as the tech tree unlocks promotions, unit development has become smoother. Atom bombs are weak, compared to earlier games, which makes them more tempting to use on the battlefield. The victory conditions of previous games remain, and the choice between Conquest, Domination, Space, Diplomatic or Cultural victory might not be apparent until the latter half of the game. Warnings when foreign civilizations approach victory, add some dearly needed end-game excitement. The game supports scripted events, too. You may call it artificial flavor, it will surely be useful in scenario making.
In general, Civ VI has the gameplay balance and interface finish of Civ 4, the accessibility of CivRev and the tactical excitement of Civ 5. It shows that RTS gaming is not about graphic resolution or number of features, but about strategic depth. And we cannot avoid to mention that the victory movie credits contain the words "Look out for Civilization VI: Heroic Epic. Expansion pack 1, coming 2014."