Warfare

From Stellaris Wiki
Jump to navigation Jump to search

Version

Outliner top.png
Please help with verifying or updating older sections of this article. At least some were last verified for version 3.5.

This article is for the PC version of Stellaris only.

As long as there is at least one empire present that is not Fanatic Pacifist.png Fanatic Pacifist, war is an almost inevitable aspect in any game and can be anything from a small border skirmish to a massive interstellar war of conquest. Wars are how mid-game and end-game borders are usually drawn.

When an AI empire is about to declare war it will first shift fleets towards the border of the target. Targeted empires that have any military intel on the aggressor will receive a warning, with higher military intel levels providing a more accurate estimate on when war will be declared.

Casus belli and wargoals[edit | edit source]

In order for an empire to start a war, it needs a Diplomacy status casus belli holder.png Casus Belli – a reason to declare war. Each casus belli grants access to at least one type of wargoal, which represents the purpose of the war. Once a war is declared, the attacked empire has a year to choose its wargoals.

Status quo effects do not include the defender's capital. In case of status quo the defender will retain its capital system regardless of occupation.

Casus belli and wargoals Requirements Surrender acceptance Victory effect Status quo effect
Claim
  • Diplomacy war.png Conquer
Existing claims on the target's systems
  • −10 per system
  • −100 per colonized system
Gain control of all systems with claims from the loser, even if not occupied. All systems occupied by the loser are returned, regardless of claims. Each side keeps all systems they have fully occupied if they have claims on them.
Counterattack
  • Diplomacy war.png Counterattack
  • Resolution mutual defense.png Mutual Defense resolution 3
  • No.pngGalacticCommunity mainButton single.png Target is not a member of the Galactic Community
  • Diplomacy war.png Target is at offensive war with a Galactic Community member
0 Gain control of all systems with claims from the loser, even if not occupied. All systems occupied by the loser are returned, regardless of claims. Each side keeps all systems they have fully occupied if they have claims on them.
Animosity
  • Diplomacy opinion.png Humiliate
  • Rivalry
−25 Gain 100 Influence.png Influence. Loser loses all of its Influence.png Influence, gains Influence.png −33% monthly influence gain and Mod pop happiness.png 10% happiness for 10 years. If the loser had the Supremacist Supremacist Diplomatic Stance policy, it is changed to Diplomatic stance belligerent.png Belligerent. Each side keeps all systems they have fully occupied if they have claims on them.
Imperial Rebuke
  • Diplomacy opinion.png Imperial Rebuke
  • Rivalry and Galactic Emperor
−25 Gain 100 Influence.png Influence. Loser loses all of its Influence.png Influence, gains Influence.png −33% monthly influence gain and Mod pop happiness.png 10% happiness for 10 years. If the loser had the Supremacist Supremacist Diplomatic Stance policy, it is changed to Diplomatic stance belligerent.png Belligerent. None
Ideology
  • Diplomacy force ideology.png Impose Ideology
  • Menu icon policies.png War philosophy policy set to Liberation Wars
  • No.pngGestalt consciousness.png Target is not a Gestalt Consciousness
−100 Loser is forced to shift ethics towards those of the victor and will leave a federation if it's part of one. Its ruler is also replaced. Authority is also shifted to that of the winner unless the winner has Auth corporate.png Corporate authority. If at least 1 colonized system is fully occupied, then all systems fully occupied by the attacker will be turned into an empire with the attacker's ethics.
Despoliation
  • Diplomacy war.png Plunder
Civic barbaric despoilers.png Barbaric Despoilers civic −25 Take 250 Energy.png Energy and Minerals.png Minerals from the loser for every planed they control, even if they didn't have enough. Loser gets −20% Energy.png Energy and Minerals.png Minerals for 10 years.

During the war, if the attacking empire invades and captures the capital of the defending empire, there is a 50% chance to steal one of the defenders owned Relics.

Each side keeps all systems they have fully occupied if they have claims on them.
Expropriation
  • Diplomacy commercial pact.png Expel Corporation
  • No.pngDiplomacy commercial pact.pngDiplomacy federation.png No shared Commercial Pact or Federation
  • Corporate empire has at least one branch office on an owned planet
−50 Corporate empire closes all branch offices on the attacker's planets. Gain 1000 Energy.png Energy per branch office. Corporate empire closes all branch offices on the attacker's planets. Corporate empire gains 1000 Energy.png Energy per branch office.
Hostile Takeover
  • Diplomacy commercial pact.png Seize Assets
  • Auth corporate.png Both empires have Corporate authority
  • Target has at least one branch office
  • No.pngCivic criminal heritage.png Criminal Heritage civic
−75 All branch offices on planets whose owners have a commercial pact or federation with victor are transferred to the victor. If loser is part of a federation, branch offices on other members' planets are kept. None
Claim the Galatron
  • Diplomacy closed borders.png Take Galatron
  • R galatron.png Target empire has the Galatron relic
  • Menu icon policies.png War philosophy policy set to Unrestricted Wars
  • No.pngGestalt consciousness.png Gestalt Consciousness
−40 Gain the Galatron relic and 100 Influence.png influence. Loser loses all of its Influence.png Influence and gains Influence.png −33% monthly influence gain and Mod pop happiness.png −10% happiness for 10 years. Attacker gains 1000 Energy.png energy.
Galatron Access Denied
  • Diplomacy closed borders.png Seize Galatron
  • R galatron.png Target empire has the Galatron relic
  • Target empire has closed borders
  • No.pngCivic machine assimilator.png Driven Assimilator civic
  • No.pngCivic fanatic purifiers.pngCivic devouring swarm.pngCivic machine terminator.png Genocidal
−40 Gain the Galatron relic and 100 Influence.png influence. Loser loses all of its Influence.png Influence and gains Influence.png −33% monthly influence gain and Mod pop happiness.png −10% happiness for 10 years. Attacker gains 1000 Energy.png energy.
Trial of Advancement
  • Diplomacy seize council seat.png Council Seat
  • Target is a member of the Imperial Council
  • Resolution create council.png By Trial of Advancement resolution
−100 Replace the loser in the Imperial Council. None
Punishment
  • Diplomacy opinion.png Humiliate
  • Diplomacy opinion.png Stop Atrocities
  • Diplomacy opinion.png Outlaw AI
  • Diplomacy opinion.png Cleanse Holy Worlds
  • Diplomacy opinion.png Decontaminate Border Territories
  • Origins elder race.png Only available to fallen empires
  • Either the fallen empire's demand was refused or they were rivaled
0 The refused demands are enforced. If the losing empire is not a Gestalt consciousness.png Gestalt Consciousness, its ruler will also be killed by the winning fallen empire, unless they are the Ancient Caretakers. Loser loses all of its Influence.png Influence, gains Influence.png −33% monthly influence gain and Mod pop happiness.png 10% happiness for 10 years. If the loser had the Supremacist Supremacist Diplomatic Stance policy, it is changed to Diplomatic stance belligerent.png Belligerent. None

Subjugation wargoals[edit | edit source]

Subjugation wargoals seek to end the independence of the targeted empire. If it has any subjects, the effects will apply to them as well. And if the loser is part of a Federation, it will leave it.

Casus belli and wargoals Requirements Surrender acceptance Victory subjugation Status quo effect
Subjugation
  • Diplomacy isvassal.png Vassalize
  • Diplomacy istributary.png Make Tributary
  • Diplomacy istributary.png Make Subsidiary
Superior relative power to the target empire.
  • No.pngCivic machine assimilator.png Driven Assimilator civic
  • No.pngCivic fanatic purifiers.pngCivic devouring swarm.pngCivic machine terminator.png Genocidal
−100 Diplomacy isvassal.png Subject (initial terms of agreement and Trade cat loyalty.png Loyalty depend on the Subjugation War Terms policy) if at least 1 colonized system is fully occupied then all systems fully occupied will be turned into a new empire and the victory conditions will be imposed upon it.
Hegemon
  • Diplomacy federation.png Establish Hegemony
Federation hegemony.png President of a level 3+ Hegemony federation
  • No.pngDiplomacy federation.png Target is not in federation
−100 Federation hegemony.png Hegemony member
Scion
  • Diplomacy isvassal.png Bring Into Fold
Origins scion 1.png Scion origin −100 Diplomacy hasvassal.png Scion of the same overlord
Imposed Inclusion
  • Diplomacy pathofchains.png Bring Into Fold
Become the Crisis Become the Crisis ascension perk −100 Diplomacy isvassal.png Subject (initial terms of agreement and Trade cat loyalty.png Loyalty depend on the Subjugation War Terms policy)
Imperial Crusade
  • Diplomacy imperial crusade.png Force Into Imperium
Resolution galactic market.png Imperial Crusade resolution −100 GalacticEmpire mainButton.png Galactic Imperium member

Paired wargoals[edit | edit source]

The following wargoals are paired together. If an empire starts a war with either of the paired wargoals the defender will automatically use the other wargoal and cannot pick another one. In case of the Allegiance War casus belli all empires which swore secret fealty to the attacker will join the attacker's side.

Paired wargoals with −1000 surrender acceptance lead to a Total War. In Total Wars, all occupied systems automatically change ownership. Their new owner will be the participant with the highest claim count on it or the occupier if none of their allies claim the system.

Casus belli and wargoal 1 Casus belli and wargoal 2 Requirements Surrender acceptance Victory effect Status quo effect
Subject
  • Diplomacy integrating.png Independence
Subject
  • Diplomacy isvassal.png Assert Overlordship
  • Diplomacy isvassal.png Subject and overlord
  • Diplomacy federation.png Subject not in a federation with overlord
0 If the subject wins, it becomes independent and the former overlord loses all claims on the former subject's systems. The subject becomes independent and the former overlord gains claims on the former subject's systems.
Secession
  • Diplomacy integrating.png Leave Hegemony
Secession
  • Diplomacy isvassal.png Assert Hegemony
Diplomacy federation.png President refused member to leave federation 0 If the attacker wins, it leaves the federation and the president loses all claims on the former member's systems. If the president wins, both empires gain a temporary Diplomacy opinion.png −20 opinion towards each other. The attacker leaves the federation and the president gains claims on the former member's systems.
Allegiance War
  • Diplomacy secret fealty.png Secret Fealty
Allegiance War
  • Diplomacy secret fealty.png Maintain Servitude
Diplomacy secret fealty.png Secret Fealty from one of target's subjects 0 If the attackers win all empires that pledged Secret Fealty to the main attacker will become the attacker's subjects and gain +2.5 Monthly Trade cat loyalty.png Loyalty for 10 years. If the defender wins the attacking subjects will gain +5 Monthly Trade cat loyalty.png Loyalty for 5 years and cannot pledge Secret Fealty during that time. The subject cannot pledge Secret Fealty for 5 years.
Imperium
  • GalacticCommunity mainButton single.png Restore Community
Imperium
  • Galactic Imperium Crush the Rebellion
  • Nemesis.png Imperium: Spark Rebellion operation
0 Losers gain −60% Diplomatic weight.png Diplomatic Weight for 6 years. If the attackers win the Galactic Imperium becomes the Galactic Community again. If the defenders win the Galactic Imperium gains 100 Authority. All attackers leave the Galactic Imperium and form a federation.
Containment
  • Diplomacy war.png End Threat
Subjugation
  • Diplomacy isvassal.png Domination
Yes.png Awakened Empire −1000 (Total War) Victory can only be achieved by conquering all colonized systems of the opposition, ending the opposing empire. If a defeated empire had starbases in uncolonized systems that were not conquered, they are removed, making the territory neutral again. Each side keeps all conquered systems.

In case of the Existential Expulsion war goal, uncolonized systems become neutral during the war.

Purification
  • Diplomacy war.png Cleansing
Civic fanatic purifiers.png Fanatic Purifiers or Civic machine terminator.png Determined Exterminator
Hunger
  • Diplomacy war.png Absorption
Civic devouring swarm.png Devouring Swarm
Sublimation
  • Diplomacy war.png Assimilation
Civic machine assimilator.png Driven Assimilator
Existential Expulsion
  • Diplomacy pathofblood.png Wipe Them Out
Become the Crisis Become the Crisis ascension perk
Colossus
  • Diplomatic rival mutual icon.png Colossus
Stop Colossus
  • Diplomatic rival mutual icon.png Stop Colossus
Apocalypse.png Either empire has a Colossus
Preemptive War
  • Diplomatic rival mutual icon.png Preemptive War
Self-Defense
  • Diplomatic rival mutual icon.png End Threat
  • Resolution mutual defense.png Mutual Defense resolution 5
  • No.pngGalacticCommunity mainButton single.png One empire is not a member of the Galactic Community
Crisis War
  • Diplomacy pathofblood.png Crisis War
Crisis War
  • Diplomacy pathofblood.png Crisis War
  • Resolution declare crisis.png Declare Crisis resolution
  • No.pngResolution declare crisis.png Repeal Crisis resolution
Event
  • Leviathans.png War in Heaven
Event
  • Leviathans.png War in Heaven
Leviathans.png Awakened Empire
Event
  • Synthetic Dawn.png Machine Uprising
Event
  • Synthetic Dawn.png Machine Uprising
Synthetic Dawn.png Creator empire and AI rebellion −1000 (Total War) Victor gains 2000-6000 Unity.png Unity and 200-600 Influence.png Influence. Victory can only be achieved by conquering all colonized systems of the opposition, ending the opposing empire. If a defeated empire had starbases in uncolonized systems that were not conquered, they are removed, making the territory neutral again. Each side keeps all conquered systems.

Claims[edit | edit source]

While casus belli and wargoals represent the purpose of a war, claims represent territorial ambitions — the systems which will be controlled by the victor. Which systems can be claimed depends on an empire's Menu icon policies.png War Philosophy policy, with the Unrestricted Warfare philosophy allowing for the claiming of any system not owned by a fellow Diplomacy federation.png Federation member. It is possible to claim the same system multiple times to gain a stronger claim on it, which can outbid the competing claims of allies when going to war together. If multiple empires have the same number of claims on a system the oldest claim is considered the strongest. In general claims are expensive in the early game and become less so later on to allow for more decisive wars to be fought. Claims cannot be rescinded while at war.

Claims have a base cost of 50 Influence.png influence, modified by the following:

  1. Additive costs:
    • +25 per hyperlane distance from owned territory
    • +25 if the system has an upgraded Spaceport 1.png Starbase (i.e. not just an Outpost)
    • +25 if the system is colonized
  2. Additive multipliers:
    • +100% Diplomacy war.png during an offensive war
    • –10% Agenda Expansionist Overtures Ruler.png Ruler agenda
    • –10% Menu icon policies.png Diplomatic stance belligerent.png Belligerent or Supremacist Supremacist Diplomatic Stance policy
    • –10% Tech interstellar campaigns.png Interstellar Campaigns technology
    • –10% Tech galactic campaigns.png Galactic Campaigns technology
    • –10% Federation military.png Martial Alliance federation level 2 perk
    • –10% Militarist.png Militarist ethic
    • –15% Civic nationalistic zeal.png Nationalistic Zeal civic
    • –20% Fanatic Militarist.png Fanatic Militarist ethic
    • –20% Interstellar Dominion Interstellar Dominion ascension perk
    • –20% R khans throne.png Khan's Throne relic
  3. –20% Diplomacy rivalry.png if the system is owned by a Rival (multiplicative, after other multipliers)

If the modifier reaches a total of –100%, claims then cost 0 Influence.png influence.

Defenders can freely claim systems owned by their attackers in a defensive war regardless of their War Philosophy policy. Any system lost by any side during a conquest war or total war will give the former owner 10 claims on it.

Winning war with any non-conquest wargoals will always enforce all claims made by the victorious empires before any other effects, regardless of whether these systems were occupied. For example, an empire winning a war with the subjugation wargoal will annex all claimed systems from the loser before making a Diplomacy isvassal.png Vassal of the loser's remaining systems.

Federation warfare[edit | edit source]

The Federation is the more serious counterpart of the Defensive pact and the inviting attackers mechanic. While it does offer a unique amount of defensive cooperation, builds trust and allows military cooperation using the federation fleet, establishing a conquest strategy can be made very difficult because of the need for consent of the members to declare war, and each member's expectation of a fair share of spoils from each war. The empire that wishes to declare war can ask the other federation members for their war goals by using the "Suggest Demands" button. However, AI empires will be very hesitant to declare war on empires that are much stronger than them or have very powerful allies. In that case, the "Suggest Demands" button will not give any results.

One exception to this are wars of liberation or to a lesser extent vassalization: usually AI will agree to a liberation war even if all the war goals are assigned to the player. The resulting splinter empire could then be vassalized and later integrated by the player.

In case a federation member is attacked, all allies automatically join the war as defenders without need for a further declaration of war. In this case, the member being attacked has a free hand in choosing federation war goals, which might be all in its own favor.

War exhaustion[edit | edit source]

War Exhaustion goes from 0% to 100%, and measures the total weariness and attrition suffered by all empires on one side in a war. War exhaustion goes up from suffering losses during space and ground warfare, destruction of planets (either from Colossus weapons or Bombardment armageddon.png Armageddon Bombardment), and a passive accumulation over time called Attrition. When a side's war exhaustion hits 100% they can be forced into a status quo peace after 24 months. The speed at which war exhaustion accumulates is influenced by factors such as ethics, traditions, technology and the amount of claims being pressed - an empire that is fighting to hold onto a handful of border systems will tire faster in a costly conflict than one whose very independence is being threatened. War exhaustion also means that an empire that is losing a war can still fight to minimize their territorial losses by inflicting high war exhaustion on the enemy.

War exhaust gain can be reduced by the following:

Source Reduction
Civic media conglomerate.png Media Conglomerate civic −5%
Civic nationalistic zeal.png Nationalistic Zeal civic −20%
Tech interstellar campaigns.png Interstellar Campaigns technology −10%
Tech galactic campaigns.png Galactic Campaigns technology −10%
Diplomatic stance belligerent.png Belligerent diplomatic stance −10%
Supremacist Supremacist diplomatic stance −20%
Gestalt consciousness.png Gestalt Consciousness ethic −20%
Resolution rules of war.png Rules of War resolution 2 −5%
Resolution rules of war.png Rules of War resolution 3 −10%
Resolution rules of war.png Rules of War resolution 4 −15%
Resolution rules of war.png Rules of War resolution 5 −20%
Tradition unyielding never surrender.png Never Surrender tradition −25%
Menace.png Crisis level 2 −75%

Ending wars[edit | edit source]

Wars can end in two ways: With the surrender of either side or with a negotiated Status Quo peace.

Surrender means that the victor's wargoal is enforced; any claims the winning side has on the losing side are automatically ceded regardless of occupation status and the defeated empire is forced to keep borders open towards the attacker for 10 years. All wars except those of independence have a negative surrender acceptance, which are countered by factors such as relative navy strength (up to +50), war exhaustion (up to +100) and occupation percentage (up to +100). If an empire and all of its allies (if any) has lost control of all of its systems and/or planets during the war, then a surrender will occur automatically.

Status Quo means that the war has reached a point where neither side is able to score a decisive victory against the other or all wargoals have been achieved decisively before any major battles took place, and both sides agree to cease hostilities and settle for whatever gains or losses they have acquired/suffered. Under a Status Quo peace, all fully occupied systems claimed by a belligerent empire are ceded to the belligerent with the strongest claim. In the case of a tie, whoever has the oldest claim on the system is considered the stronger claimant. In addition both sides must keep their borders open towards each other for 10 years. Since AI won't surrender to a Total War, they can end only in Status Quo or the destruction of one empire. Status Quo can be enforced by either side as soon as 24 months have passed since the opposing side reached 100% war exhaustion, and if both sides reach 100% war exhaustion, the Status Quo is enforced automatically after 24 months.

War names[edit | edit source]

Wars will always be named after the attacker and the defender, followed by one of the following names depending on the wargoal:

Name Wargoal Other requirements
War Any Offensive war against a Fallen Empire
  • Federation War
  • Galactic War
  • Great War
  • War of the Alliances
Any War between two Federations
  • Annexation Attempt
  • Territorial Invasion
  • War of Aggression
  • War of Conquest
Conquer
  • War of Beliefs
  • War of Ideologies
  • War of Philosophies
Impose Ideology
  • Border War
  • Confrontation
  • War of Humiliation
  • War of Rivalry
Humiliate Regular empire
Punitive Expedition Humiliate Fallen Empire
Anti-AI Police Action Outlaw AI
Buffer Zone Creation Decontaminate Border Territories
Holy Purge Cleanse Holy Worlds
Moral Intervention Stop Atrocities
  • Freedom Struggle
  • Independence War
  • Secessionist War
  • War of Independence
  • War of Liberation
Independence
  • Servitude Campaign
  • War of Obedience
  • War of Overlordship
  • War of Subjugation
Vassalize
Tributary War Make Tributary Not Auth corporate.png Corporate authority
Enforced Sponsorship Make Tributary Auth corporate.png Corporate authority
The War In Heaven War in Heaven
  • Intervention War
  • Preemptive Action
  • Preventative War
  • Self Protection War
End Threat
  • War of Cleansing
  • Xeno Filth Removal
  • Xeno Purification
Cleansing Civic fanatic purifiers.png Fanatic Purifiers civic
  • Extermination Campaign
  • Organic Disinfection Program
  • Organic Euthanization War
Cleansing Civic machine terminator.png Determined Exterminator civic
  • Absorption War
  • Biomass Accumulation
  • Great Gorging
Absorption Civic devouring swarm.png Devouring Swarm Civic
Machine Uprising Machine Uprising
Subsidiary Acquisition Make Subsidiary
Hostile Takeover Hostile Takeover
  • Embargo War
  • Expulsion War
  • War of Expropriation
Expel Corporation
War for the Galatron Take Galatron
Crisis War Crisis War
  • Menace.png Crisis level 5
  • OR
  • Resolution declare crisis.png Declare Crisis resolution
Game concepts
Exploration ExplorationFTLAnomalyArchaeological siteRelicsPre-FTL speciesFallen empireEventsSpaceborne aliensGuardiansMaraudersCaravaneers
Celestial bodies Celestial bodyColonizationTerraformingPlanetary featuresPlanet modifiers
Species SpeciesTraitsPopulationPop modificationSpecies rightsEthics
Governance EmpireGovernmentCivicsPoliciesEdictsLeaderFactionsTechnologyTraditionsSituations
Economy EconomyPlanetary managementDistrictsBuildingsHoldingsJobsDesignationTradeMegastructures
Diplomacy DiplomacyRelationsGalactic communityFederationsSubject empiresIntelligenceAI personalities
Warfare WarfareSpace warfareLand warfareStarbaseShipShip designerCrisis
Others The ShroudL-ClusterUnique systemsPreset empiresAI playersEaster eggs