City Building (series)

A city's population is confined to housing plots designated on the map by the player. Empty plots are soon developed by arriving immigrants. Each house belongs to a discrete quality level which affects, among other things, the amount it pays in taxes to the city, and the number of residents it can accommodate. Initially, housing for new residents is of the most basic quality.

Houses will upgrade to the next quality level when the specific needs for their current level are met. This is called "housing evolution". These needs can be either commodities, services, or local desirability. The player is informed of the needs of any particular house, and so can act accordingly. Better overall housing quality benefits the city - not only better houses pay more taxes, but also draws in more people to the same residence, expanding workforce while saving space. It's often recommended to players to incentive housing upgrade instead of building numerous housing separately.

When houses reach a luxury quality level, their residents stop contributing to the city workforce. This can lead to labour shortages and industrial stagnation, so the player must be careful to ensure that some houses do not evolve past this threshold, even though the tax benefits are great. In later games, starting with Zeus, housing classes are separated. As a result, housing of a given class can only advance to the peak of that class's housing quality; to obtain luxury housing and tax-heavy aristocrats, it is instead necessary to establish separate elite housing plots for them to move into. In Caesar IV, the housings are further divided into two different classes of workers as well as the non-working elites.

The original model requires that buildings needing employees be sited close to where people live in order to establish a physical connection through walker contact. This mechanism is absent from Zeus onwards.

Some houses at particular housing quality levels require certain services before they can evolve to the next level.

Services are provided by service buildings; access to these buildings has evolved through the games. In the first few games, services were distributed by zone of effect, with access determined entirely by absolute distance to the facility. In later games, a service building employs a "walker". The walker will leave the service building and walk along connected roads, taking a random direction at every intersection. Eventually the walker will return to the service building directly, and the activity will repeat. As of Caesar IV, this was changed to a walking distance measure, whereby access is determined by the distance to the building following the roads; actual distance is irrelevant if the shortest route by road is still too long.

A house is said to be supplied by a particular service if the walker from that service has recently walked past the house. If a walker from the same service does not walk past again within a particular time frame, the house is no longer supplied by the service and may return to lower quality levels.

The particular services differ from game to game, but all operate under this principle and all are common only with water distribution.

Some houses at particular housing quality levels require certain commodities before they can evolve to the next level, just as they do services.

A commodity can be obtained by the city through industrial production, or trade. Some commodities require manufacture from a raw material which in turn must be obtained from the environment. Pottery in Pharaoh, for example, is manufactured at a Potter from Clay, which is obtained at a Clay Pit. If the city does not have local supplies of a raw material, it may be able to import it and then manufacture the finished product. Alternatively, it can import the finished product directly, but this is usually much more expensive than manufacturing the goods locally.

Commodities, when produced or imported, are stored in warehouses. From there they are distributed to retailers, which employ walkers. When a retailer walker walks past a house which requires a certain commodity, the house draws a small amount from the retailer's stockpile. This amount declines over time, and so is topped up every time the walker walks past, subject to availability.

If a house runs out of a particular commodity, it may devolve to lower quality levels.

Food is treated as a commodity, though there are some differences. Food comes in many different types, some with different sources. Most food can be produced on farms, but other food can be obtained through hunting and fishing. In most cases, food is stored at granaries instead of warehouses.

Houses at particular housing quality levels require a certain variety of foods before they can evolve to the next level. However, houses are not fastidious about which specific foods are supplied. The only exception is Zeus and its expansion, in which food is a universal commodity, making it possible to feed and evolve housing with a single food source, but variations are recommended as contingency or if they're a trading opportunity. In general, food variety affects overall city health.

All industry is entirely state-controlled, with all employees being paid by the city treasury. Industry is necessary for the production of commodities. Industrial buildings must be connected to the city labour pool before they can become operational, which is done through a walker. When built, the industrial building will send out a walker along connected roads. If this walker passes occupied housing, the building is connected.

For a price, trade routes can be set up between cities. This allows the player to import commodities that may not be available in their city, or export for profit commodities that he is producing in excess. Different cities buy and sell different commodities, and these limitations are an integral aspect of the difficulty of particular campaign missions.

Trade can be conducted by land, using trading posts which caravans reach to, or water, which trading ships reach a dock, and some cities only trade by one of these methods, further adding to the complexity.

Religion is a service, which employs priests at temples as walkers. However, religion also operates on another level. The player must ensure that the gods in their civilization's religion are appeased, and is able to do so by making sure that the number of temples for each god is adequate for the city population, and ensuring that all houses are supplied by religious services.

The precise mechanism by which this aspect of religion operates differs from game to game. In Zeus, the player constructs massive temples, known as sanctuaries, to honor the gods. The god whose sanctuary is constructed will then give great benefits onto the player's city so long as the sanctuary is staffed and given the necessary sacrifices of either food or animals. Depending on its size, a city in Zeus could support up to four sanctuaries, with the player being given a selection from the Greek pantheon. The player also has the option to pray for a god's unique assistance via their sanctuary, although sometimes the god will provide the service independently if there is a need for it. Conversely, unfriendly gods can invade a city, attacking walkers and cursing or destroying buildings. In some cases, an unfriendly god will unleash a monster within a city's territory.

In Caesar III, the player has to build temples as the population grows. A particular god will be pleased with a number of temples for a long time provided that the population does not grow, but when it does, it expects from the player to increase the number of temples.

In Emperor: Rise of the Middle Kingdom, the player has to give gifts to "Heroes"; if they are pleased enough, they will visit the city, provide benefits such as reduction in building costs, and walk around. There are four groups of Heroes: the Ancestral Heroes, the Daoist Heroes, the Confucian Heroes, and the Buddhist Heroes. Failure to keep the Ancestral Heroes content can result in disasters like earthquakes or floods.

In Pharaoh the player's city has a patron god and several local gods who must all be appeased. This is done by constructing unmanned shrines for minor coverage, staffed temples to provide citizen access to religion, and temple complexes for additional benefits. Festivals can be held to increase favor with one god. Pleased gods will grant miracles, such as extra goods or production speed, while displeased gods will cause disasters, such as the collapse of buildings or plague.

While the focus of the city resides on infrastructure building, in some maps the players are forced to keep a strong military, either for defense or to conquer other cities. Military units are created at forts, and require weapons and other goods (like wood or horses), depending on the unit. In Zeus, the larger part of the army is composed by common citizens, and calling for war will have them leaving the city and their jobs. In both Zeus and Emperor: Rise of the Middle Kingdom the number of army units that are possible to build depends on the number of elite houses.

It is also possible to build defense structures, such as walls, gates, and towers.

First introduced in Pharaoh, the player is often required to erect historic monuments to increase their city's 'Monument' rating or to fulfill a goal. However, unlike normal buildings, which are built instantly, the monuments are gradually built from the ground up, through massive deliveries of construction materials (Like Sand or Plain Stone, in Pharaoh) as well as 'guilds' of special constructors whom work with a certain type of material. For an instance, when making a Pyramid, stonemasters work with Sand and Plain Stone to place and later gravel the stone, but carpenters and wood are needed to build ramps which peasants from a Work Camp can use to then haul stone loads towards the current level. However, in Pharaoh, before actual construction can begin, the player must first lay down the site and then Work Camp peasants will prepare it, digging the base into water level. Some particular monuments, like the sphinx, need only a stonemaster to quarry the monument, but all share the fact they take long amounts of time to build, even with the closest materials and personnel available, as well as they need an early massive amount of resources, made or imported via trade.

In Zeus, monuments are replaced by Sanctuaries to each god and goddess of Olympus, in which only three materials are used (Marble, wood and bronze sculptures) and all work is done by artisans from an Artisans' Guild. However, prior to building the Sanctuary, the site placement has not only a cost of drachmas (The game's currency), but also mined marble for the base and floor. This is further expanded in the Poseidon expansion, with the introduction of Black Marble and Orichalc, as well as the construction of some stepped pyramid-like monuments. Building these sanctuaries, however, is beneficial and encouraged, as the adored gods and goddesses can walk across the city, blessing structures along the way, each type according to said god/goddess (Athena, as a prime example, can bless Olive Oil industries, boosting production). Some gods can even intervene directly in case of attacks by hostile gods, monsters or rival armies.

In Emperor: Rise of the Middle Kingdom, monuments count as goal, scores as well as they're a permanent appeasement to the ancestral heroes according to each temple. Each of them varies in material types and guilds, the most common being the Field Camps, as well as three other guilds - Carpenters (Which require and work with wood), Ceramists (Which require clay, not ceramics) and Masons (Which require Stone). Each guild, however, consumes a large amount of workforce, much akin defenses and military in 'Zeus', so anticipated preparation, as well as shutting down some industry or a whole segment, is often needed.