What are the requirements for Summon to War in CK3?

The character you target: Is at not War, Is an Adult and No valid target within range. (patch 1.20.1.2)

How do I get the AI to accept Summon to War?

Accepted automatically in some cases; otherwise the AI weighs it. Its reasons: My House is a Powerful Family -10, My House is a Dominant Family -25, Your House is a Powerful Family +10, Your House is a Dominant Family +25, You are my Friend +10, You are my Guardian +10, Relative House Family Rating, Relative House Level of Splendor, Your Faith is …, Faith Hostility to Realm State Rite, …-… Cultural Acceptance, …-… Cultural Acceptance, The recipient's Military Power, Promised Title Men-at-Arms, The other character's Military Power and Already at War -1,000.

Interaction · Diplomatic actions

Summon to War

from 750PrestigeAccepted automatically in some cases; otherwise the AI weighs it

Summon the recipient to go to War with a foreign Ruler for a Duchy-tier Title

What you need

You

To send it

The target:
- Title already created
- Title tier exactly Duchy
- holder.top_liege != scope:actor

To see it in the menu

you has administrative government mechanic
Is an Independent Ruler
Your government is not Adventurer

The character you target

To send it

Is at not War
Is an Adult
… must have the Frontier Administration or Naval Administration Theme Administration Types
No valid target within range

To see it in the menu

they has administrative government mechanic
Their government is not Adventurer
… must have the Frontier Administration or Naval Administration Theme Administration Types
top_liege ?= scope:actor.top_liege

Which title you can pick

The target:
- Title already created
- Title tier exactly Duchy
- … is not neighbor with … realm

Summon to War is a diplomatic character interaction in Crusader Kings III. The character you target needs: Is at not War, Is an Adult and No valid target within range. Accepted automatically in some cases; otherwise the AI weighs it. Reasons the AI weighs include My House is a Powerful Family (-10), My House is a Dominant Family (-25), Your House is a Powerful Family (+10) and 4 more. It costs Prestige (from 750). Patch 1.20.1.2, from game/common/character_interactions/06_ep3_interactions.txt.

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Quick answers (3)

What are the requirements for Summon to War in CK3?: The character you target: Is at not War, Is an Adult and No valid target within range. (patch 1.20.1.2)
How do I get the AI to accept Summon to War?: Accepted automatically in some cases; otherwise the AI weighs it. Its reasons: My House is a Powerful Family -10, My House is a Dominant Family -25, Your House is a Powerful Family +10, Your House is a Dominant Family +25, You are my Friend +10, You are my Guardian +10, Relative House Family Rating, Relative House Level of Splendor, Your Faith is …, Faith Hostility to Realm State Rite, …-… Cultural Acceptance, …-… Cultural Acceptance, The recipient's Military Power, Promised Title Men-at-Arms, The other character's Military Power and Already at War -1,000.
How much does Summon to War cost?: Prestige (from 750) (patch 1.20.1.2).

Will they accept?

Accepted automatically when:

They use their Hook on …

Otherwise the AI adds these up and accepts above zero; near zero the answer is partly random (ai_maybe). Reasons in italics are the script's, with no label in the game.

Reason	Amount
Base	0
My House is a Powerful Family when Your house: `is_powerful_family = yes`	-10
My House is a Dominant Family when Your house: `is_dominant_family = yes`	-25
Your House is a Powerful Family when Your house: `is_powerful_family = yes`	+10
Your House is a Dominant Family when Your house: `is_dominant_family = yes`	+25
Their opinion of you × 0.5	varies
You are my Friend when Has you as friend	+10
You are my Guardian when Has you as guardian	+10
Relative House Family Rating when `house.house_head.top_liege ?= scope:actor.house.house_head.top_liege`	varies
Relative House Level of Splendor when `scope:recipient.dynasty.dynasty_prestige_level != scope:actor.dynasty.dynasty_prestige_level`	varies
Your Faith is … when Your faith: `faith_hostility_level = { target = scope:actor.faith value >= faith_astray_level }`	varies
Faith Hostility to Realm State Rite when Your rite: `rite_hostility_level = { target = scope:actor.top_liege.primary_title.state_rite value >= faith_astray_level }`	varies
…-… Cultural Acceptance when Your culture is the same as that of actor `scope:recipient.culture.cultural_acceptance(scope:actor.culture) < 50`	varies
…-… Cultural Acceptance when Your culture is the same as that of actor `scope:recipient.culture.cultural_acceptance(scope:actor.culture) >= 50`	varies
The recipient's Military Power	scope:recipient.current_military_strength
Promised Title Men-at-Arms when The option “title maa” is chosen	scope:actor.current_military_strength
The other character's Military Power	varies
Already at War when Is at War	-1,000

Acceptance (ai_accept) (134 lines of game script)

base = 0
modifier = {
	add = -10
	desc = MY_HOUSE_IS_POWERFUL
	house ?= {
		is_powerful_family = yes
	}
}
modifier = {
	add = -25
	desc = MY_HOUSE_IS_DOMINANT
	house ?= {
		is_dominant_family = yes
	}
}
modifier = {
	scope:actor.house = {
		is_powerful_family = yes
	}
	add = 10
	desc = YOUR_FAMILY_IS_POWERFUL
}
modifier = {
	scope:actor.house = {
		is_dominant_family = yes
	}
	add = 25
	desc = YOUR_FAMILY_IS_DOMINANT
}
opinion_modifier = {
	opinion_target = scope:actor
	multiplier = 0.5
}
modifier = {
	add = 10
	desc = youre_my_friend_tt
	has_relation_friend = scope:actor
}
modifier = {
	add = 10
	desc = youre_my_guardian_tt
	has_relation_guardian = scope:actor
}
modifier = {
	exists = scope:actor.house
	exists = scope:recipient.house
	house.house_head.top_liege ?= scope:actor.house.house_head.top_liege
	add = {
		value = scope:actor.house.house_power_score
		subtract = scope:recipient.house.house_power_score
	}
	desc = RELATIVE_FAMILY_RATING
}
modifier = {
	exists = scope:actor.house
	exists = house
	scope:recipient.dynasty.dynasty_prestige_level != scope:actor.dynasty.dynasty_prestige_level
	add = {
		value = scope:actor.dynasty.dynasty_prestige_level
		subtract = scope:recipient.dynasty.dynasty_prestige_level
		multiply = 10
	}
	desc = RELATIVE_FAMILY_RENOWN
}
modifier = {
	faith = {
		faith_hostility_level = {
			target = scope:actor.faith
			value >= faith_astray_level
		}
	}
	add = {
		value = faith.faith_hostility_level(scope:actor.faith)
		multiply = -10
	}
	desc = FAITH_HOSTILITY_LEVEL
}
modifier = {
	exists = scope:actor.top_liege.primary_title.state_rite
	rite = {
		rite_hostility_level = {
			target = scope:actor.top_liege.primary_title.state_rite
			value >= faith_astray_level
		}
	}
	add = {
		value = rite.rite_hostility_level(scope:actor.top_liege.primary_title.state_rite)
		multiply = -5
	}
	desc = FAITH_HOSTILITY_LEVEL_STATE_FAITH
}
modifier = {
	culture != scope:actor.culture
	scope:recipient.culture.cultural_acceptance(scope:actor.culture) < 50
	add = {
		value = 50
		subtract = scope:recipient.culture.cultural_acceptance(scope:actor.culture)
		multiply = -0.25
		round = yes
	}
	desc = CULTURAL_ACCEPTANCE
}
modifier = {
	culture != scope:actor.culture
	scope:recipient.culture.cultural_acceptance(scope:actor.culture) >= 50
	add = {
		value = scope:recipient.culture.cultural_acceptance(scope:actor.culture)
		subtract = 50
		multiply = 0.25
		round = yes
	}
	desc = CULTURAL_ACCEPTANCE
}
modifier = {
	add = scope:recipient.current_military_strength
	desc = RECIPIENT_MILITARY_STRENGTH
}
modifier = {
	add = scope:actor.current_military_strength
	scope:title_maa = yes
	desc = PROMISED_TITLE_MAA
}
modifier = {
	add = {
		value = scope:secondary_recipient.top_liege.current_military_strength
		multiply = -1
	}
	desc = SECONDARY_RECIPIENT_MILITARY_STRENGTH
}
modifier = {
	is_at_war = yes
	add = -1000
	desc = ALREADY_AT_WAR
}

As written in game/common/character_interactions/06_ep3_interactions.txt.

What happens

If they accept

If
- The option “title maa” is chosen
Then
- Your primary title:
  transfer_owned_maa_control = scope:recipient.primary_title
The character you target:
- start_war = { … }
- … war will target the …, which will be granted to … upon victory
Event ep3_interactions_events.0210

If they refuse

The character you target: Influence -100
If played by the AI: Opinion: Refused Summons to War
Event ep3_interactions_events.0211

Options when sending

Promise Imperial Men-at-Arms
Use a Hook

Events it fires: ep3_interactions_events.0210, ep3_interactions_events.0211

• the game's own tooltip text · ◦ our reading of the script line · code the script where neither exists

Who can use it and sees it (is_available, is_shown) (20 lines of game script)

is_available = government_has_mechanic = administrative
top_liege ?= this
NOT = {
	government_has_flag = government_is_landless_adventurer
}
is_shown = scope:recipient = {
	government_has_mechanic = administrative
	NOT = {
		government_has_flag = government_is_landless_adventurer
	}
	custom_tooltip = {
		text = admin_theme_type_trigger
		OR = {
			vassal_contract_has_flag = admin_theme_frontier
			vassal_contract_has_flag = admin_theme_naval
			vassal_contract_has_flag = celestial_province_protectorate
		}
	}
	top_liege ?= scope:actor.top_liege
}

As written in game/common/character_interactions/06_ep3_interactions.txt.

Can be sent when (is_valid…) (39 lines of game script)

scope:actor != scope:recipient
scope:recipient = {
	is_at_war = no
	is_adult = yes
	custom_tooltip = {
		text = admin_theme_type_trigger
		OR = {
			vassal_contract_has_flag = admin_theme_frontier
			vassal_contract_has_flag = admin_theme_naval
			vassal_contract_has_flag = celestial_province_protectorate
		}
	}
	custom_tooltip = {
		text = admin_vassal_war_no_target_desc
		trigger_if = {
			limit = {
				OR = {
					vassal_contract_has_flag = admin_theme_frontier
					vassal_contract_has_flag = celestial_province_protectorate
				}
			}
			any_character_to_title_neighboring_duchy = {
				holder ?= {
					top_liege != scope:actor.top_liege
				}
			}
		}
		trigger_if = {
			limit = {
				vassal_contract_has_flag = admin_theme_naval
			}
			any_character_to_title_neighboring_and_across_water_duchy = {
				holder ?= {
					top_liege != scope:actor.top_liege
				}
			}
		}
	}
}

As written in game/common/character_interactions/06_ep3_interactions.txt.

Effects (on_send, on_accept, on_decline) (35 lines of game script)

on_accept = if = {
	limit = {
		scope:title_maa = yes
	}
	scope:actor.primary_title = {
		transfer_owned_maa_control = scope:recipient.primary_title
	}
}
scope:recipient = {
	start_war = {
		cb = influence_war_cb
		target = scope:secondary_recipient
		claimant = scope:recipient.top_liege
		target_title = scope:target
	}
	custom_tooltip = frontier_influence_war_interaction_target_title_tt
}
scope:actor = {
	trigger_event = ep3_interactions_events.0210
}
on_decline = scope:recipient = {
	change_influence = major_influence_loss
}
scope:actor = {
	if = {
		limit = {
			is_ai = yes
		}
		add_opinion = {
			modifier = refused_summons_to_war_opinion
			target = scope:recipient
		}
	}
	trigger_event = ep3_interactions_events.0211
}

As written in game/common/character_interactions/06_ep3_interactions.txt.

Category: Diplomatic actions
Cost: Prestige: from 750
Again on the same character: after 10 years
In the menu: under More…
ID: frontier_influence_war_interaction

Source: game/common/character_interactions/06_ep3_interactions.txt and the English localisation, Crusader Kings III 1.20.1.2. “You” is the character who sends it (scope:actor, or a puppet acting for you); “the character you target” is the recipient.