Faith is a new resource introduced in Civilization V: Gods & Kings. It is closely related to Religion - in fact, the whole religious system is based on faith. Faith is the accumulated spiritual "power" of your civilization, which, when channeled in the right way, could lead to the creation of your own religion, and then to its widespread influence on other civilizations and City-States.
Faith is a resource in many ways similar to Culture, but even more difficult to produce - especially in the beginning of the game. It isn't normally present on terrain (except on certain natural wonders), so its main sources are found inside your cities, in the two exclusive faith-producing buildings: the Shrine and the Temple. However, Religious Beliefs may enable certain terrain types or features, or certain Improvements as well as Buildings to also produce faith. For more info on Beliefs, check the Religion article.
- World Wonders - Stonehenge and Notre Dame are two of the best sources of Faith.
- Religious City-States - Befriending them will contribute to your Faith each turn (the exact amount scales up with eras, just like Culture), and they will also give you a small amount of faith when you meet them - a surprising boon in the early game.
Later in the game, when your cities acquire a Majority Religion, Faith turns into a sort of currency, allowing you to purchase special units and buildings in your cities (via the "Purchase" menu in the city screen). Like units/buildings purchased with Gold, they will appear instantly in the city, although units can only be used on the next turn. Note that these purchases are only possible in cities which do have a majority religion! Cities which don't have one, or only have a Pantheon, do not qualify. The specific list of units and buildings available in each city depends on which Religion has a majority there. For example, if a religion whose Beliefs allow purchasing a Cathedral is a majority in City A, but not in City B, then you will be able to purchase a Cathedral only in City A. Furthermore, special religious units (Missionaries, Inquisitors and Prophets) purchased in a city belong to its majority religion, and not necessarily to the religion of your civilization!
The price of these units and buildings is uniform (with one exception - the Monastery is cheaper), but it scales up according to the era you're in. For example, they cost 200 Faith (Standard speed) in the Classical and Medieval Eras, 300 Faith in the Renaissance Era, 400 Faith in the Industrial Era, 600 Faith in the Modern Era, 800 Faith in the Atomic Era, and 1000 Faith in the Information Era.
Note also that other units and buildings, purchasable via special Beliefs, conform to the above prices as well.
Note that the Great Prophet, up to the Industrial Era, cannot be purchased! He is generated automatically, whenever you accumulate a required minimum amount of Faith.
All "spontaneous" faith spending in the game drains the entire Faith reserve of your empire! For example, whenever you found a Pantheon, or acquire a Great Prophet before the Industrial Era, your faith reserves will drop down to 0. This is especially annoying if you've been waiting for the spontaneous spawn of a Prophet, and were unlucky for some turns - then you may lose more than 50 Faith (depending on your current faith production rate).
Spending Faith after the Industrial Era
The pragmatism of the Industrial Era brings an end to the spontaneity of Medieval religion. Special units and buildings are still only purchasable with Faith, but Great Prophets aren't generated automatically anymore - they are now purchased with faith as all other units. Not only that, but other types of Great People may also be purchased with faith! To do this, however, you need first to complete specific Social Policy trees. Thus, Religion now turns into more of a social aspect of your civilization, but this allows unparalleled flexibility in forming your late-game empire. Great People tend to become quite difficult to produce in the normal way in the late game (they require more and more accumulated Great People points), and the option to instantly purchase them with faith is a welcome addition to your strategic options.
The price of Great People (all except the Great Prophet, whose price progression continues the same) starts at 1000 Faith (on Standard speed), and grows by 500 after each purchase. Note that it doesn't depend on the era you're in, as is the case with normal units and buildings, which allows you to continue purchasing until the very end of the game. Here is a list of the Social Policy trees and the Great People they allow you to purchase:
- Tradition: Great Engineers
- Honor: Great Generals
- Commerce: Great Merchants
- Exploration: Great Admirals
- Rationalism: Great Scientists
- Aesthetics: Great Writers, Artists and Musicians
A good rate of Faith generation is essential for any civilization that is willing to make use of Religion. Without faith, you risk to not even manage to found your own Religion; or to spread it later. As mentioned before, having a religion won't do you much good if it's only majority in two or three cities.
The most critical period for faith production is the early game. Unlike the other major stats, faith isn't produced initially by anything either in your capital, or on the terrain around it. So, unless you get lucky and find a faith bonus in some Ancient Ruins, you will need to research Pottery and build a Shrine in the very beginning of the game. Even this might not be enough - you will manage to found a Pantheon for sure with one Shrine, but you may not succeed in founding a Religion. Do the math - generating 1 Faith per turn means it'll take you at least 200 turns to get a Great Prophet. So, you have several options:
- Play as a Civilization that has a unique faith-generating advantage, such as the Celts, the Maya, or Ethiopia.
- Choose an appropriate Pantheon Belief, so that you can start producing Faith from the terrain, or from improvements. Desert Folklore works great if you're near deserts; Dance of the Aurora works if you're near tundra; and then there are a number of other Beliefs which add faith yield to either some specific resources, or specific improvements.
- Build the Stonehenge Wonder.
- Find a natural wonder with Faith yield (thankfully, there's a bunch of these), then settle a city near it and put a Citizen to work its tile. Remember - to get the faith, you need to work that tile!
It gets easier when you reach the Medieval Era. You can research Theology for the opportunity to build a number of nice religion-oriented, faith-producing Wonders. Don't miss this chance! And then, of course, equip all your cities with Shrines and Temples to ensure a steady faith growth. And if you're still lacking in faith production for some reason, try to choose some Beliefs which add faith to other buildings, such as Liturgical Drama or Divine Inspiration, when founding or enhancing your Religion.
There are cases when you don't actually need to produce lots of Faith. After you Found a Religion, Enhance it, and then spread it somewhat, your uses for the resource start to dwindle. Even if you have an appropriate Belief to purchase special buildings, you may find yourself in a situation when you have these buildings in every city, and are reduced to spamming Missionaries and Prophets. This may not be that useful, since every one of them costs Gold to maintain, and their only use at that point will be to convert City-States (which many times proves very difficult). So, don't go crazy and obsessed about producing Faith unless you have good uses for it in the middle and late game (such as the ability to purchase useful Great People).