Megastructures

Version

This article has been verified for the current PC version (4.0) of the game.

Humanoid Dyson Sphere under construction

Megastructures are colossal constructions. Expensive and time-consuming to build or repair, these remarkable feats of engineering are nonetheless important wonders that provide large bonuses, demonstrating the technological and economic primacy of the builders' empire. They cannot be built in orbit of a celestial object that has an uninvestigated anomaly. All megastructures except Gateways are destroyed if a Star-Eater destroys the system and cannot be restored after.

Construction

All megastructures require a construction ship for their initial stage; later stages do not. Many megastructures have different visual textures depending on the ship appearance of the empire that built or restored them.

Each stage of a megastructure has a required time to build measured in days. By default, construction progress is equal to 1 per day. The following factors modify this, generally increasing the rate such as progress might be 1.5, 2, or even more per day. Thus, a megastructure stage that requires 3600 days (10 years) can be completed in fewer than 3600 days.

Megastructure construction speed0
Source	Effect
Isolated Contingency Core relic triumph	+300%
Master Builders ascension perk	+50%
Architectural Renaissance ambition edict	+50%
Living Metal Mega-Construction edict	+50%
Void Hive civic	+10%
Secrets of the Cybrex empire modifier	+10%
Galactic Doorstep origin	+5%

FTL megastructures

FTL megastructures can only be constructed at the edge of a system and allow fleets to traverse to an identical megastructure, greatly easing travel across the galaxy. They work together with the FTL megastructures of another empire unless borders are closed or the empires are at war with each other. FTL megastructures can be constructed in any system which doesn't already have that type of megastructure. They can also be dismantled if the empire has the technology to build them and is at peace. Unlike other megastructures, they can be constructed in the systems of subjects as well.

Gateways

Real scale of a Gateway

While exploring the galaxy, empires may find abandoned gateways that were once part of a massive, galaxy-spanning network. The number of abandoned gateways can be scaled or disabled by galaxy settings. Note that even if gateways are disabled, at least one gateway will exist in the galaxy if any empire has the Galactic Doorstep or Imperial Fiefdom origin.

Once an abandoned gateway is discovered, the Gateway Activation technology can be drawn; this technology allows abandoned gateways to be repaired. Repairing an abandoned gateway takes 2 years and costs 6000 energy and 2500 alloys. When a gateway is activated for the first time in the galaxy, another random gateway is also activated along with it.

Once the Gateway Activation technology is researched, the Gateway Construction technology can appear, which allows new gateways to be constructed. Gateway construction first requires a construction ship to build a gateway site, which must be located outside of the system's gravity well. The gateway site takes 3 years to complete and costs 75 influence and 2500 alloys; this occupies the construction ship throughout the process. Once the site is complete, upgrading to a fully functional Gateway takes another 5 years and costs 6000 energy and 2500 alloys, but this does not require a construction ship.

Gateways allow travel to any other gateway instantly, so long as the borders are open and the destination is not controlled by an enemy empire. As a bypass, Gateways generally act like a hyperlane connection between systems, such that claims and trade can be extended through them, however sectors do not extend through gateways. Dismantling a gateway costs 2500 Energy and takes 1 year.

Repairing any gateway has a 20% chance to discover the legendary paragon, Skrand Sharpbeak; this chance increases to 50% on subsequent repairs or if the planet Skravird has been discovered. If the empire has the Galactic Doorstep origin, the chance is 33% for the first gateway and 67% for subsequent gateways or if Skravird has been discovered.

L-Gates

L-gates are a special type of gateway, with a separate network from regular gateways. Instead of jumping from any to any, L-Gates all jump to the Terminal Egress system in the L-Cluster, then from there to any other L-Gate, so long as that system's borders are open or the fleet's owner is at war with the system's owner. L-Gates are opened through a special project, and new L-Gates cannot be constructed.

Hyper Relays

Real scale of a Hyper Relay

Hyper Relays can be constructed once the Hyper Relays technology is researched and allow ships to jump to Hyper Relays in adjacent systems instead of using the existing hyperlane connections, thereby avoiding having to traverse systems at sublight speeds. They are constructed directly in a single stage, taking one year and costing 25 influence, 500 alloys, and 100 rare crystals. Hyper Relay links are shown on the galaxy map as a thicker hyperlane. Potential (inactive) links are shown as yellow connections on the galaxy map. A link may be inactive because of closed borders, war, or if the Hyper Relay is ruined. Dismantling a Hyper Relay costs 500 Energy and takes 1 year; empires with the

Scavengers

Scavengers
Refurbishment Division

civic gain 50 alloys, and 10 rare crystals.

Hyper Relays can grant additional effects based on edicts and subject specializations. Hyper Relay edicts require the empire's capital system to be part of the network, while the benefits granted by subject specializations require a connection between the overlord's capital and the subject's capital. Subjects do not benefit from their overlord's network effects.

Hyper Relays can be built from the galaxy view, which places them semi-randomly within the system. In systems with wormholes or existing gateways, it is recommended to instead go into the system view to manually place the Hyper Relay near to the wormhole or gateway to better facilitate travel, as Hyper Relays do not connect through wormholes or gateways.

Habitats

Mammalian habitat central complex

Habitats are colonizable megastructures that can be built above stars or planets and are finished in a single stage. Each system can only have one habitat. Building a habitat requires the Orbital Habitats technology, costs 200 Influence and 1500 Alloys and takes 5 years to construct. The habitat still requires colonization, but the colony develops twice as fast as on planets. Habitats cannot be built in systems with a ring world, above moons, or above celestial objects with another megastructure.

The maximum number of districts that a habitat can have is 0.25 per planet or star in the system for each habitat tier. The maximum number for each type of resource district depends on the Energy, Minerals and Research deposits in the system (deposits of unity and rare resources count as research for this purpose). Each deposit grants (1 + half of its value) districts, rounded down. Each time a resource district is constructed it creates an orbital on a celestial body with its resource if any is still available, replacing any existing mining or research station. Orbitals are identical in effects and upkeep to mining and research stations but cannot be attacked by fleets. Habitats do not have planetary features with the exception of a few unique habitats.

Only Gestalt Consciousness, Void Dwellers or empires with the Voidborne ascension perk can construct housing buildings on habitats.

Habitats are shown in one of three tiers in the outliner, depending on the level of the capital building.

Tier	Building	Habitability	Max districts per planet or star	Branch Office building slots	Required pops	Required technology
I	Habitat Administration	40%	+0.25	+1	0	Orbital Habitats
II	Habitat Central Control	50%	+0.5	+2	1000	Habitat Expansion
III	Habitat System Control	60%	+0.75	+3	2500	Advanced Space Habitation

The following unlock the ability to build habitats:

• If the Utopia DLC is active, any empire can research the technologies to construct and upgrade habitats.
• Empires with the Void Dwellers origin start with a habitat and the technology to build more. They can research the technology to upgrade them from the start.
• Empires with the Knights of the Toxic God origin start with a habitat. They can research the technology to build more from the start but cannot research the technology to upgrade them without the Utopia DLC.
• Empires with the Payback origin can gain a unique size 10 habitat called Recovered Asset as one of their two choices following the conclusion of the The Aftermath of Battle archaeological site. Choosing the habitat unlocks the technology to build more but cannot research the technology to upgrade them without the Utopia DLC.
• If the Apocalypse DLC is active, empires created by the Horde breaking up start with the technology to construct habitats. These habitats can be captured by other empires.

Habitats can otherwise be obtained in the following ways:

• The Federation's End unique system can randomly spawn, containing two habitats. The system does not require any DLC to spawn but does not contain enough celestial objects to support districts.
• If the First Contact DLC is active, the Ithome cluster has a 25% chance to spawn. The Ithome's Gate system contains 3 habitats. Each habitat has a unique modifier granting it max Habitability and +8 Reactor, Mining or Research districts.
• If the Cosmic Storms DLC is active, a habitat can be obtained by completing the Hold the Line archaeological site.

Habitat Central Complexes can be ruined by a colossus or crises. If ruined, all orbitals are destroyed.

Deep space citadels

Tier 3 deep space citadel

Deep space citadels are large defensive stations that can contain certain starbase buildings and can support defense platforms. Similar to a starbase, when a deep space citadel runs out of hull points it is occupied if the attacker was an empire and destroyed if the attacker was a crisis or using the Existential Expulsion casus belli.

Normally only Fallen Empire systems have deep space citadels, but if the BioGenesis DLC is enabled all empires can research the technology to construct their own. Deep space citadels can be constructed anywhere in a system. Each system can have one deep space citadel, and the number is increased by one for each of the following:

• Mega-Engineering technology
• Eternal Vigilance ascension perk
• Starlit Citadel origin

Deep space citadels are designed in the ship designer and when constructing or upgrading one there will be a prompt to choose which design to use. Their cost is not affected by the installed components. Deep space citadels come in three tiers. They are constructed at tier I and then upgraded. Deep space citadels can have their design changed if the empire has the technology to build them but the current construction or upgrade cost much be paid again.

Tier	Buildings	Weapon slots	Utility slots	Mechanical cost	Biological cost	Build time
I	1	3 3 9	1 8	2500 1000	2500 500 1750	3 years
II	2	6 6 9	2 16	2500 1250 100	2500 625 2188 100	3 years
III	4	1 9 6 9	3 24 1	5000 3500 500	5000 1750 6125 500	4 years

Orbital rings

Mammalian orbital ring with shipyard module

Half megastructure and half starbase, orbital rings can be built around colonized planets to act as an additional starbase in the system or provide useful bonuses for the planet below. They do not require a construction site and are finished in a single stage by the construction ship. Tier 2 and 3 are upgraded similarly to starbases without the need for a construction ship. Orbital rings also have +100% fire rate.

Tier	Mechanical cost	Biological cost	Time	Upkeep	Modules	Buildings	Platforms	Hull	Armor	Weapons range	Weapons	Utilities	Requirements
1	50 1000	50 500 1750	720	2	2	0	2	5000	1000	+100%	1 3	2 1	Orbital Rings technology
2	100 1500	50 750 2625	900	3	3	1	4	10000	2000	+150%	2 6	4 1	Star Fortress technology Tier II capital or Planetary Ascension tier 3
3	150 2000	150 1000 3500	1080	4	4	2	6	20000	2000	+200%	3 9	6 1	Citadel technology Tier III capital or Planetary Ascension tier 5

Ruined Orbital Rings can be rebuilt at a cost of 500 alloys and 50 influence and 2 years of construction time. This does not require a construction ship. A ruined Orbital Ring can be discovered in a random binary system.

Modules

Orbital Rings use their own set of modules, which are mostly similar to Starbase modules except that they do not interact with trade routes in any way. An Orbital Assembly Complex holding on the planet provides additional bonuses to each module.

	Module	Time	Cost	Upkeep	Effects	Orbital Assembly Complex bonus	Required technology
	Orbital Anchorage Fleet anchorages are necessary to support the growth of our navy.	180	50	1	+4 Naval capacity +2 with Naval Logistics Office building	+2 Naval capacity
	Orbital Vivarium Tank External tanks partially exposed to space that can safely house captured Space Fauna.	180	50	1	+10 Vivarium capacity +10% Space fauna growth rate		Gravity Snares
	Habitation Module High-speed space elevators allow the planet to extend its habitation, resource storage and refinement facilities into orbit.	360	200 25	2	+1 Max district for the planet	+0.5 Max district for the planet	Anti-Gravity Engineering

Fleet modules

Fleet modules allow the orbital ring to construct fleets. Multiple fleet modules may be constructed to produce multiple ships or space fauna in parallel but only one type of fleet module can be constructed on an orbital ring. Each fleet module costs 50 alloys, takes 180 days to construct and has an energy upkeep of 1 unit per month. Each fleet module can produce two ships or space fauna at a time instead of one if an Orbital Assembly Complex is constructed on the planet.

	Module	Can produce			Vivarium capacity	Requirements
		Civilian ships	Military ships	Space fauna
	Orbital Shipyard A Shipyard may build one ship at a time, in parallel with other Shipyards.
	Orbital Hatchery Hatcheries incubate Space Fauna Genetic Material we have collected and produce viable new specimens under our control. We can produce more powerful creatures by collecting more advanced genetic samples with our Gravity Snares.				+5	Artificial Breeding technology Beastmasters Beastmasters Space Ranchers Wild Swarm Biodrones
	Orbital Beastport Beastports are specially modified Hatcheries that can both clone Space Fauna and construct basic Civilian Ships.				+5	Beastmasters Beastmasters Space Ranchers Wild Swarm Biodrones

Defense modules

Defense modules increase the orbital ring's effectiveness in combat and allow for the construction of additional defense platforms. Each defense module costs 50 alloys, takes 180 days to construct and has an energy upkeep of 1 unit per month.

	Module	Weapons added	Other effects	Orbital Assembly Complex bonus	Required technology
	Planetary Defense Guns Adds two medium-size weapon slots to the Orbital Ring.	+2 Medium	+20% Orbital ring armor hit points +20% Orbital ring hull points +1 Defense platform cap	+1 Defense platform cap
	Planetary Defense Batteries Adds two guided weapon slots to the Orbital Ring.	+2 Guided			Space Torpedoes
	Planetary Defense Hangars Adds a hangar for Strike Craft to the Orbital Ring.	+1 Hangar			Carrier Operations

Buildings

In addition to most of the regular starbase buildings, Orbital Rings can construct a set of buildings that improve the planet's output. All of them take 360 days to build.

	Building	Cost	Upkeep	Planet effects	Requirements
	Climate Optimization Stations Detailed monitoring of local conditions means we can influence the planet's climate at a regional level, increasing agricultural yields.	100 100	2 1	+2 Food per 100 Farmers	Advanced Food Processing
	Low Gravity Mega-Refiners Centralizing mineral refining operations on the Orbital Ring allows for novel techniques that increase mining efficiency.	100 100	2 1	+2 Minerals per 100 Miners	Advanced Mineral Purification
	Stratospheric Ionization Elements These devices dramatically reduce power loss during distribution, increasing overall generator output.	100 100	2 1	+2 Energy per 100 Technicians	Planetary Power Grid
	Alloy Processing Facilities Alloys from the surface are further processed in orbit, creating usable materials from what would otherwise be wasted by-products.	200 300	5 2	+1 −2 per 100 Metallurgists If Catalytic Catalytic Processing Catalytic Recyclers Organic Reprocessing Organic Retrofitting , replaced by: +1.25 −3 per 100 Metallurgists	Nano-Separators
	Orbital Logistics Systems Transferring logistics operations to automated systems on the Orbital Ring allows planetside Factories to run continuously at full speed.	200 300	5 2	+1 −1 per 100 Artisans If Catalytic Catalytic Processing Catalytic Recyclers Organic Reprocessing Organic Retrofitting , replaced by: +1.25 −1.5 per 100 Artisans	Replicator Kiosks
	The Giga-Mall Moving all shopping and trade facilities to the Orbital Ring means our Clerks can facilitate more business, more effectively than ever before.	100 100	2 1	+1 Amenities per Trader +5% Trade value	Interstellar Economics
	Orbital Filing System Efficiency and progress can be ours once more, now that our Administrators have near instant access to the paperwork that defines their lives.	200 300	2 1	+1 Unity per 100 Bureaucrats	Effective Bureaucracy
	Synaptic Relays Portions of the Orbital Ring have been modified to enhance synaptic signals, improving control over drones on the surface.	200 300	2 1	+1 Unity per 100 Synapse Drones	Clustered Synapses
	Orbital Maintenance Drops Prepackaged pods of maintenance material - and the drones necessary to distribute them - can be dropped from orbit anywhere they are needed, at a moment's notice.	200 300	2 1	+1 Amenities per 100 Maintenance Drones	Resource Processing Algorithms
	Orbital Garden A vacuum garden for our Orbital Ring, blooming with genetically enhanced plantlife designed to attract spaceborne fauna.	50 50	1 1	+1 Food per 100 Farmers Non-hostile space fauna are attracted and collect Seed Pods Owned organic fleets collect Seed Pods if in orbit	Fruitful Partnership
	Orbital Shield Generator Hardening the shields of the orbital defenses will interfere with any planetary shields, but will allow them to hold off against more powerful weapons.	200 300	5 2	+25% Orbital ring shield hit points +25% Defense platform shield hit points	Planetary Shields technology Planetary Shield Generator on the planet

Planetary building replacements

The following orbital ring buildings fulfill the same function as certain planet buildings. They have the same requirements to construct and cannot be built if the matching building has been constructed on the planet.

	Building	Cost	Upkeep	Planet effects	Replaced building	Requirements
	Orbital Embassy Complex This orbital complex is intended to awe the viewer, rendering them more compliant in negotiations. Due to the need to be close to the seat of the government, it can only be built in orbit of our capital.	200 300	5 2	+100 Politician jobs +2 Available envoys	Embassy Complex Grand Embassy Complex	Xeno Relations technology Empire capital
	Orbital Stock Exchange By engaging in free trade of goods and services we allow for a more specialized economy, where an individual can excel in a narrow field and trade for their needs.	200 300	5 2	+100 Trader jobs +20% Trade value	Galactic Stock Exchange	Galactic Markets technology Resort World Thrall-World
	Orbital Psi Corps A segment of the Orbital Ring is devoted to training psi-gifted individuals, allowing the Psi Corps to keep a watchful eye on the planet below. The Psi Corps is your friend. Trust the Corps.	200 300	5 2	Changes Enforcers to Telepaths +5 Stability	Psi Corps	Psi Corps tradition Resort World Thrall-World
	Noble Estates Magnificent structures that take advantage of reduced gravitational effect in orbit house the local nobility. Significant portions of the ring are dedicated to their every whim.	200 300	5 2	+200 Noble jobs +200 Housing	Noble Estates	Aristocratic Elite civic Thrall-World
	Orbital Slave Processing Hub An orbital facility used to process slave labor for the planet below. Those that have been processed have any trace of free will extinguished.	200 300	5 2	+5% Slave pop resource output −25% Slave political power −50% Automatic resettlement chance Unemployed slaves automatically resettle Can recruit Slave Armies	Slave Processing Facility	Neural Implants technology Slavery policy set to Allowed Resort World

Multi-stage megastructures

Multi-stage megastructures are constructed in multiple stages that require the technology with the same name before they can be constructed. Empires lacking the technology can make use of a multi-stage megastructure which they conquered from another empire, but they cannot upgrade it before they research the prerequisite technology.

Multi-stage megastructures start with a construction site that provides no benefit. However, each subsequent construction phase brings increasing bonuses, culminating with the end of the megastructure construction.

Only one multi-stage megastructure may be built in each system. Multi-stage megastructures must be built either over an uninhabitable planet or a star. There must not be an anomaly present on the planet or star, but an anomaly on another planet or star in the system does not block construction.

Each empire can build build, upgrade, or restore only one multi-stage megastructure at a time. This limit is increased by the following factors:

Megastructure construction limit0
Source	Effect
Master Builders ascension perk	+1
Architectural Renaissance ambition edict	+1
Level 5 Research Cooperative president	+1
Arc Welders origin	+1

Most multi-stage megastructures are limited in how many times they may be built. An empire with the Isolated Contingency Core relic can build an additional megastructure of each type. If an empire loses a limited megastructure, it cannot build another of that type. Megastructures obtained through conquest and ruined ones that were found in the galaxy and repaired do not count against this limit. A conquered incomplete megastructure can still be upgraded as long as the new owner has the prerequisite technology.

Megastructure	Stage	Production	Upkeep	Time	Mechanical cost	Biological cost	Notes	Limit	DLC
Science Nexus	Site	None	−5	5 years	5000 5000	5000 2500 8750	Owning a Science Nexus may trigger the Fountain of Youth event chain and one potential outcome upgrades the Science Nexus one more stage	1
	Stage I (Hub)	+100 Research +5% Research Speed	−25	10 years	5000 15000	5000 7500 26250
	Stage II (Research Wings)	+200 Research +10% Research Speed	−50	10 years	5000 15000	5000 7500 26250
	Stage III (Completed)	+300 Research +15% Research Speed	−75	10 years	5000 15000	5000 7500 26250
	Stage IV (Groik Nexus)	+350 Research +15% Research Speed	−100	Event	Scientist	Scientist
Sentry Array	Site	None	−20	5 years	2500 5000	2500 2500 8750	Until finished, the Sentry Array cannot see through nebulae As no system will have low intel level, a completed Sentry Array will prevent space creatures from respawning A completed Sentry Array can be obtained by completing the archaeological site in the Ultima Vigilis system	1
	Stage I (Sentry Hub)	20 Sensor Range +10 Base intel level −5% Hyperdrive charge time	−40	5 years	2500 10000	2500 5000 17500
	Stage II (Sentry Spire)	40 Sensor Range +20 Base intel level −10% Hyperdrive charge time +1 Codebreaking	−60	5 years	2500 10000	2500 5000 17500
	Stage III (Sentry Aerials)	60 Sensor Range +30 Base intel level −15% Hyperdrive charge time +1 Codebreaking	−80	5 years	2500 10000	2500 5000 17500
	Stage IV (Completed)	Entire Galaxy Sensor Range +40 Base intel level −20% Hyperdrive charge time +2 Codebreaking	−100	5 years	2500 10000	2500 5000 17500
Ring World	Site	None	−5	5 years	300 5000	300 2500 8750	Cannot be built around a black hole, or in systems with multiple stars or without planets or asteroids Cannot be built if there are habitable planets or megastructures present All habitable segments feature 100% habitability for all species, can build up to 10 unique districts, and have their own unique designations Upon completion of the frame, all planets are removed from the system Multiple segments can be built at the same time if the empire has the capacity to work on more than one megastructure simultaneously Habitable segments require colonization Habitable segments can be destroyed by a Colossus or crisis and cannot be repaired	0
	Stage I (Frame)	None	None	13.3 years	10000	5000 17500
	Stage II (1 Segment)	+1 Habitable Segment	None	10 years	10000	5000 17500
	Stage III (2 Segments)	+2 Habitable Segments	None	10 years	10000	5000 17500
	Stage IV (3 Segments)	+3 Habitable Segments	None	10 years	10000	5000 17500
	Stage V (Completed)	+4 Habitable Segments	None	10 years	10000	5000 17500
Mega Art Installation	Site	None	−5	5 years	2500 5000	2500 2500 8750	The final stage requires the Ancient Relics DLC A ruined Mega Art Installation is repaired to stage 3, and can be upgraded to stage 4 as with the constructed version However, this costs 3200 and 2000 instead of the standard cost	1
	Stage I (Nascency)	+100 Unity +5% Amenities −5% Planetary ascension cost	−10	10 years	2500 15000	2500 7500 26250
	Stage II (Maturity)	+200 Unity +10% Amenities −10% Planetary ascension cost	−20	10 years	2500 15000	2500 7500 26250
	Stage III (Completed)	+300 Unity +15% Amenities −15% Planetary ascension cost	−30	10 years	2500 15000	2500 7500 26250
	Stage IV (Perfection)	+400 Unity +20% Amenities −20% Planetary ascension cost	−30	10 years	2500 2000	2500 2000
Strategic Coordination Center	Site	None	−5	5 years	2500 10000	2500 7500 8750		1
	Stage I (Hull)	+50 Naval capacity +2 Starbase capacity +4 Defense Platforms +5% Sublight speed	−25	10 years	2500 15000	2500 7500 26250
	Stage II (Comms)	+100 Naval capacity +4 Starbase capacity +8 Defense Platforms +10% Sublight speed	−50	10 years	2500 15000	2500 7500 26250
	Stage III (Completed)	+150 Naval capacity +6 Starbase capacity +12 Defense Platforms +15% Sublight speed	−75	10 years	2500 15000	2500 7500 26250
Interstellar Assembly	Site	None	−5	5 years	2500 5000	2500 2500 8750	All values stack if multiple Interstellar Assemblies are owned.	1
	Stage I (Locus)	+10% Diplomatic weight +15 Opinion from all empires	−10	5 years	2500 10000	2500 5000 17500
	Stage II (Consul Ring)	+20% Diplomatic weight +30 Opinion from all empires +1 Available envoys −5% Empire size	−20	5 years	2500 10000	2500 5000 17500
	Stage III (Forum Modules)	+30% Diplomatic weight +75 Opinion from all empires +1 Available envoys −5% Empire size	−30	5 years	2500 10000	2500 5000 17500
	Stage IV (Completed)	+40% Diplomatic weight +150 Opinion from all empires +2 Available envoys −10% Empire size	−40	5 years	2500 10000	2500 5000 17500
Matter Decompressor	Site	None	−5	5 years	5000 10000	5000 7500 8750	Can only be constructed around black holes Cannot be built if there are habitable planets or anomalies present If the black hole has a research station, it is removed when the megastructure is completed	1
	Stage I (Anchor)	+500 Minerals	−25	10 years	5000 25000	5000 18750 21875
	Stage II (Lensing)	+1000 Minerals	−50	10 years	5000 12500	5000 6250 21875
	Stage III (Boring)	+1500 Minerals	−75	10 years	5000 12500	5000 6250 21875
	Stage IV (Completed)	+2000 Minerals	−100	10 years	5000 12500	5000 6250 21875
Mega Shipyard	Site	None	−5	5 years	2500 3000	2500 1500 5250	All ships start with 100 experience Can only be built around stars in unary systems Cannot be built around pulsars, neutron stars or black holes	1
	Stage I (Framework)	+5 Shipyard Capacity +33% Empire Ship Build Speed	−10	5 years	2500 10000	2500 5000 17500
	Stage II (Core)	+10 Shipyard Capacity +66% Empire Ship Build Speed	−20	5 years	2500 10000	2500 5000 17500
	Stage III (Complete)	+20 Shipyard Capacity +100% Empire Ship Build Speed Titan and colossal ship construction	−40	5 years	2500 10000	2500 5000 17500
Quantum Catapult	Site	None	−25	5 years	300 4000	300 3000 3500	Can only be constructed around pulsars and neutron stars (including in binary or trinary systems) The accuracy of the catapult decreases with distance and is increased by upgrading the megastructure Catapulted fleets gain +33% Fire Rate for 120 days (+50% with Slingshot to the Stars origin) Quantum Catapult technology is required to use it, merely controlling it is not enough Hyper Relays technology is required for the MIA time reduction to apply If Astral Planes is enabled, the effects of the catapult can be upgraded by the Astral Calibration astral action	0
	Stage I (Single Array)	Can catapult fleets in the system −10% Missing in Action time 50 Catapult Spread 300 Catapult Range	−50	5 years	3000	1500 5250
	Stage II (Twin Arrays)	Can catapult fleets in the system −25% Catapult windup time −20% Missing in Action time 35 Catapult Spread 450 Catapult Range	−60	5 years	3000	1500 5250
	Stage III (Complete)	Can catapult fleets in the system −50% Catapult windup time −30% Missing in Action time 25 Catapult Spread 750 Catapult Range	−75	5 years	10000	5000 17500
	Stage I (Twin Arrays)	Can catapult fleets in the system −30% Catapult windup time −20% Missing in Action time 35 Catapult Spread 450 Catapult Range	−30	10 years	2500	1250 4375	Must be restored from the ruined catapult spawned by the Slingshot to the Stars origin Any Slingshot to the Stars empire can restore the special catapult without Mega-Engineering, but requires that technology to improve the catapult Other empires can restore the special catapult with Mega-Engineering
	Stage II (Complete)	Can catapult fleets in the system −60% Catapult windup time −30% Missing in Action time 25 Catapult Spread 750 Catapult Range	−50	10 years	10000	5000 17500
Arc Furnace	Stage I (Equatorial Band)	+25% Mining Station Output in system +1 Minerals on every eligible celestial object in system	−20	1 year	500 500	500 250 875	Does not add deposits to stars, astral scars, colonizable planets, and celestial objects with deposits collected by research stations Researching Mega-Engineering increases the build limit by 2 Empires with the Arc Welders origin start with a stage I Arc Furnace and can build an additional Arc Furnace above the limit If there are Trade Value deposits in the system they are removed Once the empire has the technology to build the megastructure, systems display the number of deposits that may be created by an Arc Furnace The home system of the Ancient Mining Drones has a 25% chance to spawn with a ruined Arc Furnace if the DLC is enabled Can be dismantled at the cost of 500 Energy per stage as long as the empire has the technology to construct them and is at peace	3
	Stage II (Borehole Pumps)	+50% Mining Station Output in system +2 Minerals on every eligible celestial object in system	−40	3 years	1000 1000	1000 500 1750
	Stage III (Mohole Extractors)	+75% Mining Station Output in system +2 Minerals on every eligible celestial object in system +1 Alloys on every eligible celestial object in system	−80	3 years	2000 1500	2000 750 2625
	Stage IV (Completed)	+100% Mining Station Output in system +1 Minerals on every eligible celestial object in system +2 Alloys on every eligible celestial object in system	−100	3 years	4000 2000	4000 1000 3500

Dyson Swarms and Dyson Sphere

The Dyson Swarms and the Dyson Sphere are two megastructures the construction of which may be linked depending on which DLCs are enabled. Neither megastructure can be constructed in binary or trinary systems or around pulsars, neutron stars or black holes.

• If the The Machine Age DLC is enabled, Dyson Swarms can be constructed after researching the Dyson Swarm technology
• If the Utopia DLC is enabled, a Dyson Sphere can be built after taking the Galactic Wonders ascension perk and researching the Dyson Sphere technology.
  • If the The Machine Age DLC is not enabled, a Dyson Sphere is built from scratch, starting from Construction Site
  • If the The Machine Age DLC is enabled, a Dyson Sphere is built by upgrading a completed Dyson Swarm. It upgrades to Stage II (Initial), and inherits all effects of the Dyson Swarm.
  • A ruined Dyson Sphere is always restored to Stage V (Completed), and only requires the Mega-Engineering technology to restore.
  • If the Nemesis DLC is enabled, a Dyson Sphere can be further upgraded as part of the Kaleidoscope situation.

Megastructure	Stage	Production	Upkeep	Time	Mechanical cost	Biological cost	Notes	Limit	DLC
Dyson Swarm	Stage I (Array)	+500% Star Output (×5 extra)	−5	3 years	1000 500	1000 250 875	Researching Mega-Engineering increases the build limit to 5 Can be dismantled at the cost of 500 Energy per stage as long as the empire has the technology to construct them	3
	Stage II (Constellation)	+1500% Star Output (×15 extra)	−10	3 years	2500 1000	2500 500 1750
	Stage III (Completed)	+3000% Star Output (×30 extra)	−20	3 years	5000 1500	5000 750 2625
Dyson Sphere	Site	None	−5	5 years	1000 5000	1000 2500 8750	Cannot be built in systems with a pre-FTL civilization unless the Pre-FTL Interference policy is set to Aggressive Interference Cannot be built in systems with an Arc Furnace Prevents the colonization of planets in the system Upon completion, all rocky planets and moons in the system turn into frozen or cold barren worlds If the star has a mining station, it is removed when the megastructure is completed If any planet has the Terraforming Candidate modifier, it is removed Once upgraded into a Dyson Sphere, it no longer counts against the Dyson Swarm limit	1
	Stage I (Frame)	None	None	10 years	5000 10000	5000 5000 17500
	Stage II (Initial)	+1000 Energy	None	10 years	5000 10000	5000 5000 17500
	Stage III (Medial)	+2000 Energy	None	10 years	5000 10000	5000 5000 17500
	Stage IV (Penultimate)	+3000 Energy	None	10 years	5000 10000	5000 5000 17500
	Stage V (Completed)	+4000 Energy	None	10 years	5000 10000	5000 5000 17500
	Stage VI (Wonder Sphere)	+750 Unity +30% Amenities	−30	1 year	3000 2500	3000 2500

Discoverable Ring Worlds

Up to 8 ringworlds can spawn naturally in a game in various states. Damaged segments can be repaired with the Mega-Engineering technology for the same cost as finishing a new segment.

• One in the Sanctuary system. All 4 habitable sections are intact and each contains one pre-FTL civilization, none advanced beyond Steam Age. The system was abandoned by an Enigmatic Observer Fallen Empire but contains automated defense platforms totaling over 50k fleet power.
• One in the Cybrex Alpha system. It requires completing the Cybrex precursor event chain. The ringworld is completely ruined and requires repairs on each section.
• One in the Cybrex Beta system. It is only revealed if the Contingency sterilizes 20% of the galaxy. A short time after the Contingency is defeated, the Cybrex leave the galaxy, leaving the ringworld free for the taking.
• One in a random empty system if the Utopia DLC is enabled. It is completely ruined and each section requires repairing. If the Distant Stars DLC is enabled as well, the system has a 50% chance to contain a unique anomaly.
• Three in the systems of the Ancient Caretakers if the Synthetic Dawn DLC is enabled. The ringworld in the home system has three intact and one ruined section, while the other two ringworlds are completely ruined and require each section to be repaired separately. If the Contingency appears and the Ancient Caretakers awaken to defend the galaxy, they also disappear like the Cybrex once the Contingency is defeated, leaving their systems free for the taking.
• Each empire with the Shattered Ring origin starts in a ringworld system with 1-3 segments depending on the Guaranteed Habitable Worlds game rule. By default, only one empire with the origin can be generated, but force-spawning ignores that limit.

Ruined megastructures

Ruined Dyson Sphere

Ruined versions of a multi-stage megastructure can be found while exploring the galaxy, with larger galaxies having a chance to spawn more ruined megastructures. Repairing them generally requires only the Mega-Engineering technology. If not yet researched, owning a system with a ruined megastructure also grants a ×20 weight for Mega-Engineering to appear. The following ruined megastructures cannot spawn unless the same DLC as is required to construct them is enabled.

While they upgrade from their broken to a fully functional state in one step, they do not count for any achievements. However, they also do not count against any build limit for that particular megastructure either.

Ruined Megastructure	Time	Cost	Repair technology	System notes	DLC
Dyson Sphere	20 years	20000 7500	Mega-Engineering
Science Nexus	13.3 years	15000 3200	Mega-Engineering
Sentry Array	13.3 years	15000 3500	Mega-Engineering	Contains a Tomb World
Interstellar Assembly	10 years	10000 3200	Mega-Engineering	Contains deposits on most celestial objects
Matter Decompressor	13.3 years	20000 7500	Mega-Engineering
Mega Art Installation	13.3 years	20000 3200	Mega-Engineering	Is always a trinary system
Strategic Coordination Center	13.3 years	15000 3200	Mega-Engineering
Mega Shipyard	10 years	10000 3200	Mega-Engineering
Quantum Catapult	10 years	10000	Mega-Engineering Quantum Catapult	Is always a pulsar system
Quantum Catapult	10 years	2500	Quantum Catapult	Adjacent to homeworld of a Slingshot to the Stars empire Slingshot to the Stars empires do not require the tech to restore this megastructure
Hyper Relay	6 months	500 500 100	Hyper Relays	Found in the home system of the Yuht Empire precursors
Arc Furnace	2 years	3000 2000	Arc Furnace	Can be generated in the Ancient Mining Drones home system in addition to a random system

Aetherophasic Engine

The Aetherophasic Engine is a megastructure that appears in the capital system of every empire that reaches the final Galactic Nemesis crisis level. Each stage of the megastructure requires gargantuan amounts of dark matter as well as 10 years to upgrade. If the system is conquered by another empire, the megastructure is ruined and can be repaired if the original empire reclaims it. Empires that reached the final crisis level and lost their Aetherophasic Engine but conquer another one have the option to take control of the new megastructure.

Stage					Cost	Reward if conquered ( Level 5 Galactic Nemesis)	Reward if conquered ( Level 5 Galactic Nemesis)	Effects
I	+100	+250	+100	0	0	200 Influence 5000 Alloys	10000 Dark matter	None
II	+200	+500	+150	0	20000	300 Influence 7500 Alloys	15000 Dark matter	Entering the Shroud displays a new set of messages
III	+400	+1000	+200	−1000	30000	400 Influence 10000 Alloys	20000 Dark matter	Within 1-2 years, 5% of the owned systems will be invaded by shroud avatars
IV	+800	+2000	+250	−1000	40000	600 Influence 15000 Alloys	30000 Dark matter	Within 1-2 years, 10% of the owned systems will be invaded by shroud avatars Up to 600 pops with the psionic trait die Up to 2 leaders with the psychic trait die
V	—	—	—	—	50000	—	—	Game victory The galaxy is destroyed

Synaptic Lathe

The Synaptic Lathe UI

Constructing a Synaptic Lathe requires the Scalable Reservoir Computing technology, which is unlocked by the Cosmogenesis ascension perk. Only one Synaptic Lathe can be constructed. Constructing the megastructure requires 300 Influence and 15000 Alloys and takes 2400 days.

The Synaptic Lathe has many functions normally found only on planets. It has Stability, Housing, Amenities, Pops, a designation and ascension tier. It also has an Efficiency value, which is increased by 5% for each pop. Low Stability cannot create revolts but still affects job output. The Synaptic Lathe has its own set of buildings and districts and its appearance changes as the capital building is upgraded.

All pops in a Synaptic Lathe have the Neural Chip job. Pops cannot grow on a Synaptic Lathe but they can be resettled even if the empire policy does not otherwise allow it. Pops in the Synaptic Lathe are purged over time regardless of species rights; the rate of the purge scales with the population of the Lathe. If the population drops to zero, the owner gets an event to either refill the Lathe with 100 pops, or let it break. The last pop cannot be resettled. Pops with the Virtual trait do not generate resources when placed in a Synaptic Lathe.

The Synaptic Lathe has no defenses and immediately surrenders if an enemy fleet enters orbit. The megastructure will be disabled if the occupying empire does not have the Cosmogenesis ascension perk. If the system is completely occupied, the megastructure is destroyed. The occupying empire will get the option to resettle half of the pops to the capital, gain 500-1000000 Research and −75 Decaying Opinion with every non-fallen empire, or do nothing. Empires with the Cosmogenesis ascension perk can choose to keep the megastructure instead.

Grand Archive

A Grand Archive

Constructing a Grand Archive requires the Galactic Archivism technology, takes 1800 days and costs 1000 Alloys, or 750 if the empire has a

Galactic Curators

Galactic Curators
Antiquarian Expertise
Caretaker Network
Caretaker Network

civic. The megastructure can only be constructed over worlds that have at least 2500 Pops unless the empire has the Wilderness origin. It is constructed in one stage and has a base upkeep of 10 Energy. The Grand Archive enables turning specimens into exhibits and increases Vivarium Capacity by +50. If communications with the Curator Order have been established, shortly after the megastructure is completed, the empire will receive +10 Opinion with them. Empires with the Treasure Hunters origin or a

Galactic Curators

Galactic Curators
Antiquarian Expertise
Caretaker Network
Caretaker Network

or

Beastmasters

Beastmasters
Space Ranchers
Wild Swarm
Biodrones

civic will also gain a moderate amount of scaled Unity when the megastructure is completed.

If the starbase of the system housing the Grand Archive is dismantled, the megastructure is removed. The empire will be refunded 500 Alloys and all space fauna above the Vivarium Capacity is culled.

An empire can only have one Grand Archive. If a subject with a Grand Archive is integrated while the empire already has one, the subject's megastructure is removed. If a system housing a Grand Archive is conquered, the megastructure is destroyed and all space fauna above the Vivarium Capacity is released. The empire that conquered the system will steal one specimen from each category, or two if it has the Barbaric Despoilers civic. If Ancient Relics is installed, it will also receive 100 Minor Artifacts.

Behemoth megastructures

A Behemoth Egg

Behemoth megastructures are available to empires with the Behemoth Fury ascension perk and used to create Behemoths. Hatching them requires the crisis level 2.

Megastructure	Construction cost	Hatching cost	Hatchling
Behemoth Egg	50000 300 10 years	100000 150 10 years	Class I Behemoth
Behemoth Chrysalis (class II)	Fully fed class I Behemoth	75000 3 years	Class II Behemoth
Behemoth Chrysalis (class III)	Fully fed class II Behemoth	125000 3 years	Class III Behemoth
Behemoth Egg (strengthened)	10000 2 months 1 year cooldown	90000 2 years	Class I Behemoth
Behemoth Egg (rapid)	10000 2 months 6 months cooldown	10000 6 months	Size 32 fleet (ship size depends of the Egg Development policy)
Behemoth Egg (large)	10000 2 months 1 year cooldown	40000 1 year	Size 96 fleet (ship size depends of the Egg Development policy)

Behemoth Egg megastructures are destroyed if an enraged Behemoth reaches them.

References

Game concepts