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This article has been verified for the current PC version (3.10) of the game.
Mammalian Citadel

Mammalian Citadel

A starbase is the primary space station used throughout the game and is used for determining the ownership of a star system; construction, repair and maintenance of ships; collection and transportation of Trade Value; as well as acting as a strategic fortress during warfare.

Mechanics[]

Constructing a starbase requires first fully surveying the desired system. The build cost is 100 alloys and an additional influence cost on top of that. The influence cost is a base of 75, multiplied by the number of hyperlane jumps, including bypasses, between the target systems and the empire's closest owned system. This is reduced by the Slingshot to the Stars origin, which reduces the distance multiplier by 75%. For example, an adjacent system (1 jump) costs 75 influence, a system 2 jumps away costs 150 influence, or 94 influence with Slingshot to the Stars. Other modifiers to the total influence cost can be found below.

Once built, the starbase will appear orbiting the center point of the system. It cannot be destroyed by any regular means, but it can be dismantled by its owner during peacetime if it is of no more than outpost level (higher-level starbases will need to be downgraded first) and the system is not colonized. If a starbase is dismantled, the system reverts to being neutral and unowned and can then be claimed by any empire. Crisis factions, including the Khan and Gray Tempest, destroy starbases when they reduce it to 0 hull, though it is rebuilt as an outpost if their fleet leaves and a colonized world remains in the system. Star-Eaters also destroy the starbase when they crack the star.

Besides the initial influence cost, upgrading the starbase to a higher level costs only alloys. Aside from making the starbase more powerful due to better base stats and the addition of more weapon components, the upgrade also allows the owner to fit the starbase with different buildings and modules to increase its defensive capabilities and improve its contribution to the empire beyond its basic role of system control and defense. One such important module is the Shipyard Shipyard which enables the construction of ships at the starbase. Having multiple shipyards on a starbase allows it to effectively act as a "fleet manufactory" by constructing several ships simultaneously in parallel. Shipyard build order is independent from the main build order of starbase.

Though it is not possible to design a starbase, its components will be auto-fitted with the latest advanced technology as soon as they are made available (at no additional cost to the owner).

Starbase capacity[]

The number of upgraded starbases an empire can support without penalty is determined by the starbase capacity. Every upgraded starbase exceeding that capacity adds Upkeep 25% upkeep for all starbases. This modifier also affects the upkeep of modules and buildings on starbases. Regardless of their level, each starbase above outpost level occupies only one capacity slot and if the need arises, an empire can always downgrade existing starbases back to outpost level to reduce the number of upgraded starbases to within the cap.

The base starbase capacity is 3. This is increased by 1 for every 10 owned systems and can also be increased by the following:

Source Starbase capacity
Strategic Coordination Center (stage III) +6
Grasp the Void Grasp the Void ascension perk +5
Trading Posts civic +4
Strategic Coordination Center (stage II) +4
Fortify the Border edict +2
Unyielding tradition tree +2
Fortress Doctrine Fortress Doctrine tradition tree +2
Stellar Expansion technology +2
Manifest Destiny technology +2
Strategic Coordination Center (stage I) +2
Interstellar Expansion technology (repeatable 5 times) +1

Warfare behavior[]

Systems with starbases above outpost level require a higher influence cost to claim ( 25 influence). Additionally, those starbases grant a higher war-score if occupied successfully (10 occupation value). An additional benefit of upgraded starbases comes from their including an FTL inhibitor which prevents enemy ships from leaving the system via any hyperlane other than the one they arrived through until the starbase is disabled or occupied. This allows an FTL inhibitor-equipped starbase to turn strategically important systems into efficient choke points, preventing hostile fleets from bypassing the system without engaging the starbase and thereby forcing them into an engagement which may last long enough for reinforcements to arrive.

During war, an attacker must disable the enemy's starbase within the system in order to be able to seize control of any planets within said system. As starbases cannot be destroyed, this is achieved by reducing the Health Hull points down to 0, disabling the starbase. The starbase will then remain incapacitated for a duration of Time 30 days (after the latest attack), during which time any military ships in close proximity to the starbase will be able to gain control over it. If control of the starbase is uncontested, it will enter a self-repair phase and then become operational again as soon as it regains Health 5% Hull points. When a starbase is disabled, control of the starbase will be assigned to its owner, the war participant with the strongest system claim, or the war participant with the nearest fleet, in that order.

Occupied starbases are fully operational and can repair ships of the side that controls it, inhibit FTL for "enemy" ships, and manage defense platforms, all empire-wide bonuses will also be applied, including home territory modifiers (The Eternal Vigilance Eternal Vigilance ascension perk's platform cap of the original owner is also temporarily retained). However, the buildings and modules cannot be changed, and the starbase cannot be upgraded or downgraded, although it can be returned to the owner.

It is worth noting that auto-upgrading a starbase can "gift" higher tech components to occupied starbases (including FTL inhibitors), while keeping their own more advanced components. They will stay equipped even if said starbase is reclaimed back, so repeated re-conquering might become harder for both sides.

Level[]

A starbase is auto-fitted with the latest components as soon as they are available to the empire. This is done automatically and has no additional cost for the empire - as such this also does not affect a starbase's level upgrade cost.

The weapon slots are fitted with the most effective kinetic and energy weapons (though not necessarily by equal division). The utility slots are divided equally between Shield shield and Armor armor components (auto-fitting does not add hull components here), while the Auxiliary auxiliary slot uses standard auto-fitting of a shield capacitor or auxiliary fire-control (whatever is available in order of priority).

Upgrading a starbase requires the technology of the same name and can only be done in sequential order - meaning that upgrading a basic outpost to a citadel requires going through every level in between to get to the desired level. Downgrading a starbase, however, reduces it to outpost level immediately, which removes all buildings and modules and any defense platforms over the outpost's capacity limit. Any resources invested into the starbase prior to downgrading will not be refunded.

Starting from starport level, all starbases have an FTL inhibitor if the FTL Inhibition technology has been researched.

Note: The table lists the base properties of each starbase level. The actual values themselves will differ due to one's progress in-game (technology, tradition, and etc.), existing modifiers (if any) as well as individual starbase composition (buildings, modules, and etc.).

Level Cost Time Time Upkeep Modules Buildings Defense platform cap Platforms Trade protection Health Hull Armor Armor Weapons Utilities Repairs docked fleets
Outpost 100 100 1 0 0 3 0 5000 1000 Medium 1
  • Large 2
  • Auxiliary 1
Starport 200 360 2 2 1 6 8 10000 2000 Medium 3
  • Large 6
  • Auxiliary 1
Starhold 500 720 3 4 2 9 16 20000 5000 Medium 5
  • Large 10
  • Auxiliary 1
Star Fortress 1250 1080 4 6 3 12 24 40000 10000 Medium 7
  • Large 14
  • Auxiliary 1
Citadel 3500 1440 5 6 4 15 32 80000 20000 Medium 13
  • Large 26
  • Auxiliary 1

Modules[]

A fully upgraded starbase can support up to 6 modules. It is possible to construct multiple modules of the same type and the starbase will be described in the outliner depending on the majority module type. Each module takes 180 days to construct and has an Energy upkeep of 1.

Module Cost Effects Requirements Description
Shipyard 50 +1 Shipyard Capacity A Shipyard may build one ship at a time, in parallel with other Shipyards.
Anchorage 50 Fleet anchorages are necessary to support the growth of our navy.
Gun Battery 50
  • Medium +2 Medium weapon components
  • +5 Trade Protection
  • +1 Protection Range
  • +1 Defense Platform Cap
  • Armor +10% Starbase armor hit points
  • Health +10% Starbase hull points
Adds two medium-size weapon slots to the Starbase.
Missile Battery 50
  • Guided +2 Guided weapon components
  • +5 Trade Protection
  • +1 Protection Range
  • +1 Defense Platform Cap
  • Armor +10% Starbase armor hit points
  • Health +10% Starbase hull points
Space Torpedoes Space Torpedoes technology Adds two torpedo weapon slots to the Starbase.
Hangar Bay 50
  • Hangar +1 Hangar weapon components
  • +10 Trade Protection
  • +1 Protection Range
  • +1 Defense Platform Cap
  • Armor +10% Starbase armor hit points
  • Health +10% Starbase hull points
Carrier Operations technology Adds a hangar for strike craft to the Starbase.
Trade Hub 50 +1 Collection Range Gestalt Consciousness A civilian docking area where merchants and traders can conduct business.
Solar Panel Network 50
  • +6 Energy
  • +12 total with Unchained Knowledge resolution level 2 or above
Gestalt Consciousness Advances in solar panel technology could offset the operating costs of our starbases.
Detection Array 100 +1 Detection Strength Detection Array technology Adds high-powered suite of external sensors, capable of detecting cloaked fleets.
Ancient Rampart
  • 50
  • 45
  • +2 Defense Platform Cap
  • Health +5% Defense Platform hull points
  • Damage +5% Defense Platform damage
  • Health +15% Starbase hull points
  • Without Archaeo-Engineers Archaeo-Engineers:
    • Armor +15% Starbase armor hit points
  • With Archaeo-Engineers Archaeo-Engineers:
    • Armor +20% Starbase armor hit points
    • Armor +10% Starbase armor hardening
Ancient Rampart technology Defense platforms are a cost effective way to ensure our safety, but they need to be monitored from an operation center. Fortifying our Starbase to ensure its survivability in the event of an attack, and maximizing our capacity to network independent orbital defenses would give us more time to dispatch reinforcements.

Buildings[]

A fully upgraded starbase can support up to 4 buildings. Unlike modules, it is only possible to construct a single building of any type. Building cost is reduced by −25% by the Modular Engineering technology. Many starbase buildings can also be built on Orbital Rings.

Building Cost Time Upkeep Effects Orbital Ring Requirements
Resource Silo 50 Time 180
Communications Jammer 50 Time 180 1
  • –20% Enemy Combat Disengagement Chance in system
  • –20% Enemy Sublight Speed in system
Max 1 per system
Disruption Field Generator 100 Time 180 2 Shield –20% Enemy Shield Hit Points in system Max 1 per system
Crew Quarters 50 Time 180 1 –25% Docked ship upkeep Gestalt Consciousness
Crew Gestation Chambers 50 Time 180 1 –25% Docked ship upkeep Hive Mind
Service Umbilicals 50 Time 180 1 –25% Docked ship upkeep Machine Intelligence
Fleet Academy 100 Time 360 2 +100 Ship Starting Experience
Battle Simulators 100 Time 360 2 +100 Ship Starting Experience
Black Hole Observatory 100 Time 360 2
Command Center 250 Time 360 5 +10% Allied Fire Rate in system
Deep Space Black Site 100 Time 360 2
  • +1 Unity
  • +25% System Governing Ethics Attraction
  • +5 System Stability
Defense-Grid Supercomputer 150 Time 360 2 +8 Defense Platform Cap Synchronized Defenses Synchronized Defenses
Hydroponics Bay 50 Time 180 1 +10 Food Hydroponics Farming
Hyperlane Registrar 100 Time 180 2 +1 Collection Range
Listening Post 100 Time 360 2
  • +2 Sensor range
  • +4 Hyperlane detection range
  • +1 Sensor range if Starbase has 3 Detection Array modules with Unusual Senses
  • +1 Detection strength if Starbase has 3 Detection Array modules with Unusual Senses
  • +1 Sensor and Hyperlane detection range with Unchained Knowledge resolution 2
Gravitic Sensors
Nebula Refinery 100 Time 360 2
Offworld Trading Company 100 Time 360 +2 Trade value from Trading Hubs
Transit Hub 100 Time 180 3
  • +100% Automatic Resettlement Chance for every planet in system
  • Slaves and non-sapient robots can automatically resettle from this system
Mining Bay 50 Time 180 1 +5 Minerals
Titan Assembly Yards 500 Time 720 10 Titan construction enabled
Colossal Assembly Yards 1000 Time 720 20
  • Colossus construction enabled
  • Federations Juggernaut construction enabled
  • Star-Eater construction enabled
  • Shipyard
  • Citadel
  • Colossi, Juggernaut or Star Eater technologies
Ancient Shield Overcharger 100
45
Time 360 15
2
Ancient Shield Overcharger
Interstellar Recruitment Office 50 Time 720 2
  • +1 External Leader Pool Size
  • +10% Leader Experience Gain
  • +200% Chance to be contacted by a Renowned Paragon
Dark Matter Resonance Chamber 500
25
Time 360 5
0.25
+1 Detection strength if Starbase has 3 Detection Array modules
Starseed Garden 50 Time 180 1
  • Non-hostile space fauna are attracted to the starbase and collect Seed Pods at it
  • Feature Relic-spawned Prethoryn fleets will collect Seed Pods if orbiting the starbase
Fruitful Partnership
Offspring Outlook 150 Time 180 2
  • +65% Accuracy in system
  • +65% Evasion in system
  • +65% Fire rate in system
  • +65% Sublight speed in system
  • Does not stack with Offspring ship auras
Progenitor Hive
Reloading Bay 100 Time 360 2
  • +25% Fire rate
  • +2 Defense Platform Cap
Sovereign Guardianship
Cordyceptic Reanimation Facility 100 Time 180 10
  • Creates a fleet of 8 large and 8 small Tiyanki Space Whales every 5 years if built in Tiyun Ori or Tiyana Vek
  • Creates a fleet of 12 large and 6 small Space Amoeba every 5 years if built in Amor Alveo
Dimensional Shrine 100 Time 360 3 +10 Unity
Ice Mining Station 100 Time 360
  • +15% Mining Station Output
  • Enables the Expand Planetary Sea decision
  • Hydrocentric ascension perk
  • Frozen world or ice asteroids in system
Dragon Hatchery 750 Time 720 10 Feature Allows the construction of Fledgling Dragons
Dark Matter Listening Post 500
50
Time 360 10
0.5
  • +2 Sensor range
  • +4 Hyperlane detection range
  • +6 Detection strength
Fallen Empire

Enclave buildings[]

The following starbase buildings require an agreement with an enclave and/or the enclave's presence in the system. They cannot be constructed on Orbital Rings. Enclave buildings gain a bonus if the Unchained Knowledge resolution 3 is passed.

Building Cost Time Upkeep Effects Unchained Knowledge bonus Requirements Description
Curator Think Tank 100 Time 360 2 +5 Research +5 Research
  • Agreement with the Curator enclave
  • System has a Curator station
By constructing a research facility entirely focused on learning from, and cooperating with, the Curators, we are able to make significant contributions to our scientific progress.
Art College 200 Time 360 2 +10 Unity +10 Unity
  • Agreement with the Artisan enclave
  • System has an Artisan station
This zero-g Art College, operated in conjunction with the nearby Artisan Enclave, celebrates the beauty of outer space in the works produced by its talented students.
Trader Proxy Office 100 Time 360 −5% Market fee +5 Trade value The Trader Enclaves enjoy special privileges on the Galactic Market, which can also benefit us.
Salvage Works 100 Time 360 3
  • –20% Docked ship upkeep
  • +30% Docked ship hull repair speed
  • +30% Docked ship armor repair speed
+5 Alloys
  • Overlord Agreement with the Salvager enclave
  • Overlord System has the Salvager enclave
This bustling annex equips our engineering teams with a cornucopia of tools and spare parts, facilitating closer collaboration with the nearby Salvager Enclave.
Mercenary Garrison 100 Time 360 20 +15% Allied Fire Rate in system +5 Naval capacity Overlord Agreement with a Mercenary enclave A collection of barracks hosting military contractors. These grizzled veterans organize regular drills for the rest of the crew, and stand ready to defend the station - as long as we pay them.
Shroud Beacon 500
25
Time 720 3
  • Feature Creates a Shroud Tunnel bypass
  • Feature Allows use of Shroud Tunnel bypasses
  • Overlord Agreement with the Shroud-Touched Coven enclave
  • Wormhole in system
  • Max 1 per empire
A psionic Beacon used to spawn a Shroud Tunnel in system. While the Shroud Beacon may be dismantled (or destroyed), the Tunnel itself cannot be removed.

Precursor buildings[]

The following starbase buildings can only be constructed after completing the special project to delve into the secrets of one of the precursors and researching a unique technology. They cannot be constructed on Orbital Rings. Precursor buildings gain a bonus with the Archaeo-Engineers Archaeo-Engineers ascension perk.

Building Cost Time Upkeep Effects Archaeo-Engineers Archaeo-Engineers bonus Required technology Description
Cybrex Mining Hub 100
12
Time 360 1 +100% Mining Station Output +50% Mining Station Output Cybrex Mining Hub To build their ring world, the Cybrex relied on highly efficient mining drones to survey and harvest orbital resources. Cybrex-made memory chips and sensors could outfit our own mining drones, so that we might put their millennia old algorithms to good use.
Irassian Naval Yards 100
45
Time 360 2
  • +1 Shipyard Capacity
  • +20% Ship Build Speed
+10% Ship Build Speed The Irassian astronaval tradition was unmatched in their time. Their shipyards produced a constant stream of ships for their navy and merchant fleets, which would ultimately be their downfall. With so many ships, and such a high reliance on them, the Irassians were powerless to quarantine the disease that would claim their empire.
Yuht Astronomical Interferometer 100
45
Time 360 2
  • +7 Sensor Range
  • +14 Ship Hyperlane Detection Range
  • +3 Sensor Range
  • +6 Ship Hyperlane Detection Range
Yuht Astronomical Interferometer The Yuht were a paradoxical society, obsessed with the idea of finding other sentient species, yet refusing to accept that they were not alone. They were so focused on disproving any claim of alien life, that their bias found a way into their technology. However, with the proper modifications and calibrations, we could certainly fix their powerful detection arrays.
Zroni Storm Caster 100
45
100
Time 360 20
1
Creates a Space Storm in the system Damage −10% Daily Hull to enemy ships Zroni Storm Caster Zro is a fascinating element, prone to chaotic bursts of energy. We believe that with the right artifacts, we could use it to fuel spatial storms over entire solar systems.

Defenses[]

Mammalian Ion Cannon

Mammalian Ion Cannon

Because starbases are vital targets during warfare, an empire must ensure that they can maintain control over their own starbases to prevent their opponents from seizing control of the system. Investing resources into arming a starbase can allow it to function as a strong deterrent to enemy invasions, a powerful supporting power during a fleet battle in the system, and a starbase that is heavily armed enough can potentially even repel an entire enemy fleet by itself. Successfully maintaining control over every single starbase in the empire is by itself enough to allow an empire to end the war through a status-quo without losing any systems, earning them a defensive victory.

Basic starbase defense are turrets. Starbase turrets are always of Medium medium size. Number of slots increase after each Starbase level upgrade and more can be added by building Gun Batteries. Type of weapon cannot be chosen-slots will be filled by highest possible tier of automatically chosen type of weapon. Only possibility of diversification of turrets is to add Guided guided weapon by building Missile Batteries or Hangar aircrafts weapon by building Hangar Bays. It is advised to reinforce critical starbases with defense platforms and to not rely only on turrets.

Defense platforms are smaller military stations that are deployed around the starbase and act as additional weapons platforms. They will engage any incoming hostile ships, effectively acting as a supporting weapon, by attacking and distracting them from focusing their efforts on the starbase itself, allowing the starbase to engage the enemies and support the defense platforms.

Unlike starbase auto-fitted turret design, they have two sections for weapon slots which can be outfitted with a wide variety of weapon configurations in Ship Designer, allowing for several designs to be built based on the different needs on each front and to be upgraded based on these designs. However, unlike ships, their designs cannot be switched once built, necessitating dismantling and completely rebuilding in order to change designs. It also renders any transferred platforms non-upgradeable.

When compared with ships, platforms are situated between Destroyer and Cruiser classes, their hull and armament slightly better than the former, while their armor-potential is equivalent to the latter. However, due to them having no Evasion evasion whatsoever, individual platforms are still very vulnerable, and if a strong, sustainable firepower is a priority, it is wiser to put more turrets on the base itself and only add in defense platforms once the starbases available armaments have been maxed out.

Basic capacity of defense platforms is 3. The Defense platform cap defense platform capacity for starbases can be increased by the following:

Source Defense platform cap (empire)
Strategic Coordination Center (stage III) +12
Strategic Coordination Center (stage II) +8
Bulwark tier III +8
Bulwark tier II +5
Eternal Vigilance Eternal Vigilance ascension perk +5
Strategic Coordination Center (stage I) +4
Building Vigil Command holding (subject tier III) +4
Bulwark tier I +2
Building Vigil Command holding (subject tier II) +2
Building Vigil Command holding (subject tier I) +1
Source Defense platform cap (starbase)
Citadel base level +12
Star Fortress base level +9
Defense Grid Supercomputer +8
Starhold base level +6
Starport base level +3
Ancient Rampart +2
Reloading Bay +2
Gun Battery +1
Hangar Bay +1
Missile Battery +1

Ion Cannon[]

In addition to the regular defense platforms, a citadel-level starbase is also capable of hosting an Ion Cannon, a more powerful platform type that carries a weapon identical to the Perdition Beam titan weapon. It is titan-class hull-wise, but only battleship-class armor-wise. Each Ion Cannon has an upkeep of 8 energy.

An ion cannon platform is equivalent to 8 defense platforms in terms of capacity slots and can only be constructed on citadel-level starbases.

Defense platform modifiers[]

Defense platforms have +30% Weapons Range. Additional modifiers which affect various defense platform parameters are summarized below. Note that general modifiers to ship hull, armor, shield, and damage also apply to defense platforms.

Defense platform damage Damage
+100% Bulwark Tier 3
+75% Bulwark Tier 2
+50% Bulwark Tier 1
+50% Bulwark with A Voice for All Resolution
+33% Defensive Zeal Defensive Zeal
+25% Eternal Vigilance Eternal Vigilance
+25% Agenda Secure the Borders
+10% Synchronized Firing Patterns
Defense platform hull points Hull points
+100% Bulwark Tier 3
+75% Bulwark Tier 2
+50% Bulwark Tier 1
+50% Bulwark with A Voice for All Resolution
+33% Defensive Zeal Defensive Zeal
+25% Agenda Secure the Borders
+10% Fortified Core Layers
+500 Improved Structural Integrity


Defense platform build cost Build cost
−75% Bulwark Tier 3
−50% Bulwark Tier 2
−33% Fortifier ruler trait
−25% Bulwark Tier 1
−25% Bulwark Prefabs (overlord)
−15% Agenda Secure the Borders
+25% Bulwark Prefabs (subject)
Speed Build speed
+100% Fortress Proclamation
Upkeep Upkeep
−75% Bulwark Tier 3
−50% Bulwark Tier 2
−25% Bulwark Tier 1
−25% Bulwark Prefabs (overlord)
+25% Bulwark Prefabs (subject)

References[]


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