In Rise of Nations, ramping cost refers to an additional cost for creating something (such as units or buildings) because others of the same type already exist. The more that already exist, the more expensive each additional one becomes. Its purpose is to discourage relying on mass numbers of the same unit or building and to encourage a more diverse strategy. For example, the cost of building the first Fort is 100 Wealth and 300 Metal. The cost of building the 5th Fort is 300 Wealth and 900 Metal, or 3 times the cost. This encourages players to build Forts only at the most strategically valuable locations, rather than everywhere throughout the map.
Many military units have a progressive ramping cost. This means that the ramping cost of the unit has the pattern:
1, 3, 6, 10, 15, 21, 28, 36, 45, 55, ...
or some multiple thereof. Thus, the increase in cost for the first few units is relatively inconsequential, but fielding larger armies takes substantially more resources. This means that producing a few units for defense is relatively cheap, compared with creating an invasion army. Additionally, the number of units contributing to the ramping cost is not just that type of unit alone, but is a broader classification. For example, many Barracks units such as Heavy Infantry, Light Infantry, and Foot Archers all contribute to each others' ramping costs, so building a Hoplites unit increases the cost of a Bowmen unit as well and vice versa. Some military units, such as Artillery Weapons, have a linear ramping cost.
However, the total cost of a unit (including both the base cost and this ramping cost) is usually capped at a maximum of 2.25X the base cost of the unit. Exceptions include Citizens (capped at 120 Food or 6X base cost), Scholars (capped at 630 Wealth or 21X base cost), and others.
The ramping cost includes not only the number of units built, but also the number of units queued in unit-producing buildings. The cost of the queued units do not decrease if the same type of unit dies in the field, but they will decrease if un-queued and then re-queued. Thus, it is better to use the infinite queue option or not queue up too many units if that type of unit is about to face battle.
Most buildings increase in cost linearly, based on values found in buildingrules.xml (with the base cost given as COST in increments of 10, and the ramping cost as SUPPORT0, SUPPORTVALUE0, SUPPORT1, and SUPPORTVALUE1). For example, the cost of the first University is 60 Timber and 30 Wealth, and the cost for every University thereafter increases by 20 Timber and 20 Wealth per University beyond the first, so the cost of the 6th University is 160 Timber and 130 Wealth.
However, unit-producing buildings (such as Barracks, Airbases and Missile Silos) have a different progression, and Forts have their own progression. The exception to this is the Dock, which has a linear progression. Example costs and the increases are given below. If the increase is constant, then it is a linear ramping cost.
The number of buildings includes completed buildings, buildings that are under construction, and buildings that have been placed but not yet started. If multiple buildings have been placed but not yet started, and one of them is canceled, then you receive a refund as if it were the most recently placed building. This includes buildings that have been placed but not yet started which end up canceled due to expanding enemy national borders.
The ramping cost of wonders increases by 1X a wonder's support cost for the first 3 wonders beyond the first, then 1.5X support cost for the next 3 wonders, then 2X support cost for all subsequent wonders. It also increases by 0.5X support cost for every wonder owned by an ally. It does not depend on which other wonders are already in progress or completed, only the number of wonders. For example, the cost of Pyramids, which has a base cost of 200 Food and 200 Timber and a support cost of 60 Food and 60 Timber, for different numbers of wonders owned by the player is given below:
In this example, every wonder owned by an ally would increase the cost of the Pyramids by 30 Food and 30 Timber.
More advanced wonders tend to have a higher base cost as well as a higher support cost, relative to the base cost. Thus, purely from a resource perspective, it would be cheapest to build the most advanced wonder first and then build cheaper wonders later. However, earlier wonders can be built earlier and often more quickly, and thus have more impact on the game since the wonder's benefits are in effect for more time. Strategically, the player has to balance getting the benefits of earlier wonders earlier versus the drawbacks of later wonders being more expensive if earlier wonders are built. The base cost and supporting cost of wonders are given below.
|Wonder||Base Cost||Supporting Cost|
|Pyramids||200 Food / 200 Timber||60 Food / 60 Timber|
|Colossus||200 Timber / 200 Wealth||60 Timber / 60 Wealth|
|Hanging Gardens||200 Food / 200 Wealth||60 Food / 60 Wealth|
|Terra Cotta Army||300 Food / 300 Wealth||90 Food / 90 Wealth|
|Colosseum||300 Timber / 300 Metal||90 Timber / 90 Metal|
|Forbidden City||300 Food / 300 Timber||90 Food / 90 Timber|
|Temple of Tikal||400 Food / 400 Timber||120 Food / 120 Timber|
|Porcelain Tower||400 Metal / 400 Wealth||120 Metal / 120 Wealth|
|Red Fort||400 Metal / 400 Wealth||120 Metal / 120 Wealth|
|Angkor Wat||500 Timber / 500 Wealth||180 Timber / 180 Wealth|
|Versailles||500 Food / 500 Metal||180 Food / 180 Metal|
|Statue of Liberty||600 Food / 600 Wealth||240 Food / 240 Wealth|
|Kremlin||700 Food / 700 Metal||360 Food / 360 Metal|
|Taj Mahal||600 Timber / 600 Wealth||240 Timber / 240 Wealth|
|Eiffel Tower||700 Timber / 700 Metal||360 Timber / 360 Metal|
|Supercollider||800 Food / 800 Knowledge||480 Food / 480 Knowledge|
|Space Program||800 Wealth / 800 Knowledge||480 Wealth / 480 Knowledge|
Production Time Edit
The base production time of units is 1.2 times the JOB_TIME value for that unit in unitrules.xml, plus 1, in frames. The ramping cost is 7.5 frames for each additional unit, rounding up. There is a maximum of 3 times the base production time for that unit; only the Citizen and Scholar are likely to reach this limit. More information can be found at the unit build rate page.
The time needed to construct a building does not increase with the number of buildings (there is no ramping).
An important aspect of bonuses such as nation powers and rare resources is whether they only affect the base cost, or affect both the base cost and the ramping cost. This is because in many situations, the ramping cost itself can be several times the base cost, and thus bonuses that affect both base and ramping costs are much more valuable. If a bonus affects only the base cost, the ramping cost is unaffected.
In calculating costs, usually the raw cost (base + ramping) is calculated first, then any caps are applied (such as the 2.25X base cost cap on many unit costs), and then bonuses reducing the costs are applied. For example, a Slingers unit has a base cost of 40 Food and 40 Timber. This means that its max cost is 90 Food and 90 Timber (2.25X the base cost), so the ramping cost will contribute at most 50 Food and 50 Timber. If the nation has a bonus that decreases unit costs by 10%, affecting only the base cost, then the maximum cost of the Slingers will drop to 86 Food and 86 Timber, because the base cost will become 36 Food and 36 Timber while the ramping cost stays at 50 Food and 50 Timber.
In general, bonuses affecting units will only apply to the base cost. However, they will also decrease the base cost of upgrades for that unit. The few bonuses affecting both the base and ramping parts of unit costs will not affect the unit's upgrade cost. Bonuses affecting unit upgrade costs generally decrease both the base and ramping parts, with the bonus from Wine being a major exception (it only affects the base portion). Bonuses affecting buildings and wonders will apply to both the base and ramping costs. Bonuses affecting build time will apply to both the base and ramping times. Bonuses directly decreasing the cost of resources, such as the bonus from Sugar, will decrease both the base and ramping costs, and indeed stacks multiplicatively with all other bonuses.
- The Americans' 25% cheaper ground unit upgrades includes ramping cost. The 20% cheaper aircraft and aircraft carriers is base cost only. It does not apply to missiles.
- The Bantu's 75% cheaper cities includes ramping cost.
- The British's 25% cheaper anti-aircraft units is base cost only. The 25% cheaper anti-aircraft buildings (Air Defense Gun and its upgrades) includes ramping cost.
- The Dutch's 10% cheaper ship upgrades includes ramping cost.
- The Egyptians' 25% cheaper wonders includes ramping cost.
- The French's 15% cheaper Siege Factory and Factory units is base cost only.
- The Germans' 25% cheaper fireships and submarines is base cost only. It applies to the entire line from Fire Rafts onward.
- The Greeks' 66% cheaper Libraries and Universities includes ramping cost.
- The Inca's 25% refund on killed units includes ramping cost. It is also based on the number of units (both created and in queue to be created) at the time the unit is killed, and thus the actual refund can be more than 25% of the original cost to build the unit. For example, the first Slingers unit costs 40 Food and 40 Timber. If many units are made and/or queued while it is sent out and dies, the refund can be as high as 22 Food and 22 Timber, which is 1/4 of its maximum cost of 90 Food and 90 Timber.
- The Indians' buildings have no ramping cost, except for Wonders, Towers, Lookouts, and Forts which raise at half the normal rate (meaning the ramping cost portion is half of normal), and cities which raise normally. Their Elephants being 15% cheaper does include ramping cost.
- The Japanese's 7% cheaper Barracks units per age is base cost only. The 10% cheaper ships is base cost only. The 50% cheaper Farms includes ramping cost.
- The Koreans' 33% cheaper Towers includes ramping cost.
- The Maya's 25% less building timber includes ramping cost.
- The Mongols' 10% cheaper mounted units is base cost only. The bonus also applies to Armored Cavalry and Tanks; thus, it is more accurate to say it applies to all Stables/Auto Plant units.
- The Nubians' 10% cheaper Merchants and Caravans are base cost only. The 10% cheaper Markets including ramping cost.
- The Romans' 25% cheaper Forts includes ramping cost. Roman towers also get this bonus (but Roman towers do not get the build speed bonus). The 10% cheaper Heavy Infantry is base cost only.
- The Russians' 50% cheaper Spies is base cost only.
- The Turks' 33% cheaper Citizens is base cost only.
Government Bonuses Edit
- Despotism's 15% decrease in Barracks unit cost is base cost only. However, it also decreases the base cost of unit upgrades.
- Monarchy's 25% decrease in Stables/Auto Plant unit cost includes both base and ramping costs. However, it does not decrease the cost of unit upgrades.
- Socialism's 25% decrease in Factory, Dock, and Airbase unit cost includes both base and ramping costs. However, it does not decrease the cost of unit upgrades. Although the tooltip states 20%, the actual decrease is 25%. The bonus does not affect fighter-bombers (which are built at aircraft carriers) nor missiles (which are built at missile silos).
Rare Resource Bonuses Edit
- Aluminum's 15% reduced aircraft cost is base only. It includes missiles. (The speed bonus refers to an aircraft's movement speed, and does not affect its build speed.)
- Horses' 15% reduced Stables/Auto Plant unit cost is base only.
- Marble's 10% reduced Wonder cost includes ramping cost.
- Rubber's 15% reduced Auto Plant unit cost is base only. However, unlike the stated description, it also affects cavalry (i.e. Stables units). The two bonuses will multiplicatively stack with each other, so that the base cost is 72% of original with both rare resources.
- Salt's stated 15% reduced Barracks unit cost is actually 10%, and is base only.
- Sulphur's 20% reduced Siege and Artillery unit cost is base only.
- Uranium's 5% reduced nuclear missile cost is base only.
- Wine's 20% reduced unit upgrade cost is base only.
- Wool's 15% reduced citizen cost is base only.
Technology Bonuses Edit
- Each level of Military above the level of a military unit decreases that unit's cost by 5%. This includes the ramping cost. For military unit upgrades, each level of Military above the new unit's level decreases the upgrade cost by 10%. This includes the ramping cost.