modifiers Requirement Types

Requirement Types Reference

Requirements are conditions that control when modifiers activate. This document lists available requirement types.

Overview

Requirements are combined into RequirementSets:

• REQUIREMENTSET_TEST_ALL - All requirements must pass
• REQUIREMENTSET_TEST_ANY - Any requirement can pass

Requirements can be inverted with Inverse="true".

City Requirements

REQUIREMENT_CITY_HAS_BUILDING

Checks if city has a specific building.

Argument	Type	Description
BuildingType	TEXT	Building to check for

<Requirement type="REQUIREMENT_CITY_HAS_BUILDING">
    <Argument name="BuildingType">BUILDING_GRANARY</Argument>
</Requirement>

REQUIREMENT_CITY_HAS_BUILD_QUEUE

Checks if city has a build queue (is a full city, not a town).

<Requirement type="REQUIREMENT_CITY_HAS_BUILD_QUEUE"/>

Use Inverse="true" to check for towns:

<Requirement type="REQUIREMENT_CITY_HAS_BUILD_QUEUE" Inverse="true"/>

REQUIREMENT_CITY_IS_CITY

Checks if settlement is a city (not town).

REQUIREMENT_CITY_FOUNDED_WITH_X_BIOME_TILES

Checks biome tiles at city founding.

Argument	Type	Description
BiomeType	TEXT	Biome type
Amount	INTEGER	Minimum tiles

Plot Requirements

REQUIREMENT_PLOT_BIOME_TYPE_MATCHES

Checks plot biome.

Argument	Type	Description
BiomeType	TEXT	BIOME_DESERT, BIOME_TUNDRA, etc.

REQUIREMENT_PLOT_TERRAIN_TYPE_MATCHES

Checks terrain type.

Argument	Type	Description
TerrainType	TEXT	Terrain type

REQUIREMENT_PLOT_DISTRICT_CLASS

Checks district class on the plot.

Argument	Type	Description
DistrictClass	TEXT	CITYCENTER, URBAN, RURAL, WONDER

Can check multiple:

<Requirement type="REQUIREMENT_PLOT_DISTRICT_CLASS">
    <Argument name="DistrictClass">RURAL, URBAN, CITYCENTER</Argument>
</Requirement>

REQUIREMENT_PLOT_IS_RIVER

Checks if plot is on a river.

Argument	Type	Description
Navigable	BOOLEAN	Require navigable river

REQUIREMENT_PLOT_IS_LAKE

Checks if plot is a lake.

REQUIREMENT_PLOT_ADJACENT_TO_COAST

Checks if plot is adjacent to coast.

REQUIREMENT_PLOT_ADJACENT_TO_LAKE

Checks if plot is adjacent to a lake.

REQUIREMENT_PLOT_ADJACENT_TO_RIVER

Checks if plot is adjacent to a river.

REQUIREMENT_PLOT_RESOURCE_VISIBLE

Checks if plot has a visible resource.

REQUIREMENT_PLOT_IS_HOMELANDS

Checks if plot is in player's homelands (near capital hemisphere).

REQUIREMENT_PLOT_ADJACENT_TO_OWNER

Checks if plot is adjacent to owner's territory.

Unit Requirements

REQUIREMENT_UNIT_TAG_MATCHES

Checks if unit has a specific tag.

Argument	Type	Description
Tag	TEXT	Unit class tag

<Requirement type="REQUIREMENT_UNIT_TAG_MATCHES">
    <Argument name="Tag">UNIT_CLASS_INFANTRY</Argument>
</Requirement>

REQUIREMENT_UNIT_DOMAIN_MATCHES

Checks unit domain.

Argument	Type	Description
UnitDomain	TEXT	DOMAIN_LAND, DOMAIN_SEA, DOMAIN_AIR

REQUIREMENT_UNIT_CLASS_MATCHES

Checks unit class.

Argument	Type	Description
UnitClass	TEXT	Unit class

Player Requirements

REQUIREMENT_PLAYER_IS_HUMAN

Checks if player is human (not AI).

Use Inverse="true" to check for AI:

<Requirement type="REQUIREMENT_PLAYER_IS_HUMAN" Inverse="true"/>

REQUIREMENT_PLAYER_IS_ATTACKING

Checks if player is the attacker in combat.

REQUIREMENT_PLAYER_IS_MAJOR

Checks if player is a major civilization.

REQUIREMENT_PLAYER_IS_MINOR

Checks if player is a minor civilization (city-state).

REQUIREMENT_PLAYER_HAS_COMPLETED_PROGRESSION_TREE_NODE

Checks if player has researched a tech/civic.

Argument	Type	Description
ProgressionTreeNodeType	TEXT	Tech/civic node
MinDepth	INTEGER	Required completion depth

<Requirement type="REQUIREMENT_PLAYER_HAS_COMPLETED_PROGRESSION_TREE_NODE">
    <Argument name="ProgressionTreeNodeType">NODE_TECH_AQ_MASONRY</Argument>
    <Argument name="MinDepth">1</Argument>
</Requirement>

Meta Requirements

REQUIREMENT_REQUIREMENTSET_IS_MET

Checks if another requirement set is met.

Argument	Type	Description
RequirementSetId	TEXT	Requirement set to check

<Requirement type="REQUIREMENT_REQUIREMENTSET_IS_MET">
    <Argument name="RequirementSetId">REQSET_UNIT_CLASS_INFANTRY</Argument>
</Requirement>

Database Definition

In traditional database format:

<Requirements>
    <Row RequirementId="REQ_MY_CHECK" RequirementType="REQUIREMENT_CITY_HAS_BUILDING"/>
</Requirements>
<RequirementArguments>
    <Row RequirementId="REQ_MY_CHECK" Name="BuildingType" Value="BUILDING_GRANARY"/>
</RequirementArguments>
<RequirementSetRequirements>
    <Row RequirementSetId="MY_REQUIREMENTS" RequirementId="REQ_MY_CHECK"/>
</RequirementSetRequirements>

GameEffects XML Format

In GameEffects format:

<Modifier id="MY_MODIFIER" collection="COLLECTION_PLAYER_CITIES" effect="EFFECT_CITY_ADJUST_YIELD">
    <SubjectRequirements type="REQUIREMENTSET_TEST_ALL">
        <Requirement type="REQUIREMENT_CITY_HAS_BUILDING">
            <Argument name="BuildingType">BUILDING_GRANARY</Argument>
        </Requirement>
    </SubjectRequirements>
    <Argument name="YieldType">YIELD_FOOD</Argument>
    <Argument name="Amount">2</Argument>
</Modifier>

Common Predefined RequirementSets

RequirementSetId	Description
REQSET_URBAN_PLOTS	Urban or city center plots
REQSET_RURAL_PLOTS	Rural plots
REQSET_ONLY_CITIES	Full cities only
REQSET_ONLY_TOWNS	Towns only
REQSET_BIOME_TUNDRA	Tundra biome
REQSET_UNIT_CLASS_INFANTRY	Infantry units
REQSET_UNIT_CLASS_MOUNTED	Mounted units
REQSET_UNIT_CLASS_NAVAL	Naval units
REQSET_PLAYER_IS_AI	AI players
REQSET_PLAYER_IS_MAJOR	Major civilizations

See Also

• Effect Types
• Collection Types
• Modifier System Overview