civilization creation Starting Bias

Starting Bias System

Starting bias controls where civilizations prefer to spawn on the map. The game uses multiple scoring tables to determine the best start positions for each civilization.

Overview

Starting bias is calculated by scoring potential start locations based on:

• Biomes - Climate zones (desert, tropical, grassland, etc.)
• Terrains - Elevation and type (hills, flat, rivers, etc.)
• Features - Terrain features (forests, floodplains, etc.)
• Resources - Specific resource types nearby
• Rivers - Proximity to rivers
• Coasts - Proximity to coastal tiles

Higher scores indicate stronger preference. The game sums scores from all applicable tables.

StartBiasBiomes Table

Preferences for specific climate zones:

<StartBiasBiomes>
    <Row CivilizationType="CIVILIZATION_EGYPT" BiomeType="BIOME_DESERT" Score="5"/>
    <Row CivilizationType="CIVILIZATION_GREECE" BiomeType="BIOME_GRASSLAND" Score="5"/>
    <Row CivilizationType="CIVILIZATION_KHMER" BiomeType="BIOME_TROPICAL" Score="5"/>
    <Row CivilizationType="CIVILIZATION_MAYA" BiomeType="BIOME_TROPICAL" Score="5"/>
    <Row CivilizationType="CIVILIZATION_PERSIA" BiomeType="BIOME_DESERT" Score="5"/>
</StartBiasBiomes>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
BiomeType	TEXT	Target biome
Score	INTEGER	Preference strength

Available Biomes

BiomeType	Description
BIOME_DESERT	Arid desert regions
BIOME_GRASSLAND	Temperate grasslands
BIOME_PLAINS	Open plains
BIOME_TROPICAL	Tropical/jungle regions
BIOME_TUNDRA	Cold northern regions
BIOME_MARINE	Ocean/coastal biome

StartBiasTerrains Table

Preferences for specific terrain types:

<StartBiasTerrains>
    <Row CivilizationType="CIVILIZATION_AKSUM" TerrainType="TERRAIN_HILL" Score="5"/>
    <Row CivilizationType="CIVILIZATION_EGYPT" TerrainType="TERRAIN_NAVIGABLE_RIVER" Score="20"/>
    <Row CivilizationType="CIVILIZATION_GREECE" TerrainType="TERRAIN_HILL" Score="15"/>
    <Row CivilizationType="CIVILIZATION_INCA" TerrainType="TERRAIN_MOUNTAIN" Score="15"/>
    <Row CivilizationType="CIVILIZATION_MISSISSIPPIAN" TerrainType="TERRAIN_FLAT" Score="15"/>
</StartBiasTerrains>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
TerrainType	TEXT	Target terrain
Score	INTEGER	Preference strength

Available Terrains

TerrainType	Description
TERRAIN_FLAT	Flat land
TERRAIN_HILL	Hilly terrain
TERRAIN_MOUNTAIN	Mountain tiles
TERRAIN_COAST	Coastal water
TERRAIN_OCEAN	Deep ocean
TERRAIN_NAVIGABLE_RIVER	Major rivers

StartBiasFeatureClasses Table

Preferences for terrain feature classes:

<StartBiasFeatureClasses>
    <Row CivilizationType="CIVILIZATION_KHMER" FeatureClassType="FEATURE_CLASS_FLOODPLAIN" Score="15"/>
    <Row CivilizationType="CIVILIZATION_MAURYA" FeatureClassType="FEATURE_CLASS_VEGETATED" Score="5"/>
    <Row CivilizationType="CIVILIZATION_MAYA" FeatureClassType="FEATURE_CLASS_VEGETATED" Score="15"/>
</StartBiasFeatureClasses>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
FeatureClassType	TEXT	Target feature class
Score	INTEGER	Preference strength

Available Feature Classes

FeatureClassType	Description
FEATURE_CLASS_FLOODPLAIN	River floodplains
FEATURE_CLASS_VEGETATED	Forests, jungles
FEATURE_CLASS_WET	Marshes, wetlands
FEATURE_CLASS_AQUATIC	Water features

StartBiasResources Table

Preferences for specific resource types:

<StartBiasResources>
    <Row CivilizationType="CIVILIZATION_ABBASID" ResourceType="RESOURCE_CAMELS" Score="5"/>
    <Row CivilizationType="CIVILIZATION_MAJAPAHIT" ResourceType="RESOURCE_SPICES" Score="5"/>
    <Row CivilizationType="CIVILIZATION_MING" ResourceType="RESOURCE_SILK" Score="5"/>
    <Row CivilizationType="CIVILIZATION_MONGOLIA" ResourceType="RESOURCE_HORSES" Score="5"/>
</StartBiasResources>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
ResourceType	TEXT	Target resource
Score	INTEGER	Preference strength

StartBiasRivers Table

Preference for spawning near any river:

<StartBiasRivers>
    <Row CivilizationType="CIVILIZATION_MISSISSIPPIAN" Score="5"/>
</StartBiasRivers>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
Score	INTEGER	River proximity preference

StartBiasAdjacentToCoasts Table

Preference for spawning near coastal tiles:

<StartBiasAdjacentToCoasts>
    <Row CivilizationType="CIVILIZATION_AKSUM" Score="150"/>
    <Row CivilizationType="CIVILIZATION_CHOLA" Score="150"/>
    <Row CivilizationType="CIVILIZATION_HAWAII" Score="25"/>
    <Row CivilizationType="CIVILIZATION_MAJAPAHIT" Score="150"/>
    <Row CivilizationType="CIVILIZATION_NORMAN" Score="75"/>
    <Row CivilizationType="CIVILIZATION_SPAIN" Score="150"/>
</StartBiasAdjacentToCoasts>

Columns

Column	Type	Description
CivilizationType	TEXT	Civilization reference
Score	INTEGER	Coastal proximity preference

Score Guidelines

Score Range	Meaning
1-5	Weak preference
10-20	Moderate preference
25-75	Strong preference
100-150	Very strong preference

Higher scores significantly influence spawn location. Use scores of 100+ for mandatory features (like Hawaii needing coastal access).

Example: Complete Starting Bias Setup

<?xml version="1.0" encoding="utf-8"?>
<Database>
    <!-- Desert river civ with coastal access -->
    <StartBiasBiomes>
        <Row CivilizationType="CIVILIZATION_MY_CIV" BiomeType="BIOME_DESERT" Score="10"/>
    </StartBiasBiomes>

    <StartBiasTerrains>
        <Row CivilizationType="CIVILIZATION_MY_CIV" TerrainType="TERRAIN_NAVIGABLE_RIVER" Score="20"/>
    </StartBiasTerrains>

    <StartBiasFeatureClasses>
        <Row CivilizationType="CIVILIZATION_MY_CIV" FeatureClassType="FEATURE_CLASS_FLOODPLAIN" Score="15"/>
    </StartBiasFeatureClasses>

    <StartBiasAdjacentToCoasts>
        <Row CivilizationType="CIVILIZATION_MY_CIV" Score="50"/>
    </StartBiasAdjacentToCoasts>
</Database>

Antiquity Civilization Start Biases

Civilization	Primary Bias	Score	Secondary Bias
Aksum	Hills, Coast	5, 150	-
Egypt	Navigable River	20	Desert biome
Greece	Hills	15	Grassland biome
Han	Grassland	5	-
Khmer	Tropical, Floodplains	5, 15	-
Maurya	Vegetated	5	-
Maya	Tropical, Vegetated	5, 15	-
Mississippian	Flat, Rivers	15, 5	-
Persia	Desert	5	-
Rome	Grassland	5	-

Exploration Civilization Start Biases

Civilization	Primary Bias	Score	Secondary Bias
Abbasid	Coast, Camels	25, 5	-
Chola	Tropical, Coast	5, 150	-
Hawaii	Marine, Coast	15, 25	-
Inca	Plains, Mountains	5, 15	-
Majapahit	Coast, Spices	150, 5	-
Ming	Silk	5	-
Mongolia	Horses	5	-
Norman	Coast	75	-
Songhai	Navigable River	20	-
Spain	Coast	150	-

Best Practices

1. Balance scores - Don't make all biases too strong or spawn will fail
2. Consider map types - Island maps need coastal bias, Pangaea doesn't
3. Match civ abilities - River civs should have river bias
4. Test on multiple maps - Verify spawns work on different map types
5. Combine multiple biases - Use 2-3 bias types for natural variety

Related Documentation

• Civilizations
• Map & Terrain
• Resources