This article is for the PC version of Stellaris only.
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. All of them require unlocking certain technologies to be built.
There are three types of megastructures: gateways, habitable projects and galactic wonders. Systems can only host one galactic wonder. Habitable megastructures (habitats and ringworlds) can be colonized but will be irreparably destroyed if a crisis overruns them. Galactic wonders provide massive bonuses and cannot be destroyed by any crisis, but are limited to one per empire. All megastructures have a different textures depending on the empire that built them.
It is only possible to build, upgrade, or restore one megastructure at a time, except in the case of habitats and gateways. The limit can be increased by one with the Master Builders perk, and one more with the Architectural Renaissance Ambition edict.
A construction ship is required to build the first stage of any megastructure. If the megastructure has multiple stages, the following stages do not require the construction ship.
Each megastructure is unlocked by researching the technology of the same name. An empire that conquers a system with a megastructure can use it, but if the construction was partial it will not be able to continue its construction without the required technology. Damaged megastructures found through exploration, however, can be reconstructed by unlocking the Mega Engineering technology.
A few bonuses affect megastructure construction speed. These are highly desirable considering the great time requirements of such projects:
- Master Builders ascension perk increases the build speed by +50%
- Living Metal Mega-Construction edict increases the build speed by +50%
- Architectural Renaissance unity ambition also increases the build speed by +50%
While exploring the galaxy, empires can find abandoned gateways that were once part of a massive, galaxy-spanning network. Reverse-engineered from encountered abandoned gateways, these megastructures require the Gateway Activation technology and can be used to travel directly to any other active gateway in the galaxy. Reactivation of gateway takes 2 years and costs 6 000 energy and 2 500 alloys. The Gateway Activation technology can appear as a research option as soon as a Gateway has been discovered and hyperspace slipstreamstechnology has been researched but the chance is very low. Owning a system with an inactive Gateway increases the chance for the tech to appear by 4 times.
When the first gateway in the galaxy is re-activated, another random gateway will also be re-activated along with it. As opposed to wormholes, both gateways must be owned by the same empire or two empires with open borders in order to be able to travel through them. Systems with gateways count as bordering for the purposes of diplomacy, so every opened gate increases diplomatic tension between all active gate-owners. Claims cannot be extended through gateways. Additionally, gateways are able to greatly enhance and simplify trade infrastructure.
Eventually, empires can build their own gateways by researching the Gateway Construction technology. Notice, that this tech requires having some civilization with an access to pre-existing gateways, so if gateways were disabled during galaxy creation it is impossible to build any new. Each system can have only one gateway, but black hole systems with an L-Gate can also have a regular gateway constructed. Gateways can be built in systems in which there is already a megastructure. The construction site is built in only 3 years and costs 100 influence and 2 500 alloys. Upgrading it to a gateway takes 5 years and costs 6 000 energy and 2 500 alloys.
|Available only with the Utopia DLC enabled.|
Artificial planets in all but name, habitats have a planet size of 6 to work coupled with 80% habitability for all species. Its appearance is dependent on the builders' empire appearance. The constructed habitat still requires colonization.
Habitats have a unique set of Districts distinct from normal planetary ones. Up to 3 Districts are shared among all Habitats, with a fourth one being available if the Habitat is built above a planet with a resource deposit.
The project takes 5 years to complete and costs a total of 200 influence and 3 000 alloys. Unlike other megastructures habitats do not require a construction site and are finished in one go by the construction ship.
Habitats require the Orbital Habitats technology to be built. The Voidborne Ascension Perk increases their Habitability to 100% and District Cap to 8. They cannot be built on moons or planets with an anomaly.
If a habitat is destroyed by a crisis or World Cracker it will never be possible to build another habitat on the same spot, or even a mining/research station, so any strategic resources on the planet are permanently lost.
Multi-stage megastructures are constructed in multiple stages. Almost all of them can only be constructed once. They start with a construction site that provides no benefit, however each subsequent construction phase will bring increasing bonuses, culminating with the end of the megastructure construction. Habitats and gateways can be built in the same system as multi-stage megastructures.
These Megastructures can only be built once per empire and require the technology of the same name before they can be constructed. However their bonuses are massive and they cannot be destroyed, only captured.
Galactic Wonders conquered from other empires do not count against the build limit, nor do ruined ones that are found and repaired.
Ruined Galactic Wonders
A ruined version of a Galactic Wonder can be found while exploring the galaxy, with the largest galaxies having a chance to spawn two or even three ruined Galactic Wonders. Repairing them only requires the mega-engineering technology and no ascension perks. If not yet researched, running into a ruined Galactic Wonder also grants a better chance for mega-engineering to appear as a researchable technology.
While they upgrade from their broken to a fully functional state in one step, they do not count for any achievements. However, they do not count against any build limit for that particular megastructure either. Another megastructure may also be constructed in the same system as a ruined or restored one.
|Mega Art Installation||4800||20000|
|Strategic Coordination Center||4800||15000|
- 1 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.
- 1 in the Cybrex Alpha system. It requires completing the Cybrex precursor event chain. The ringworld is completely ruined and requires repairs on each section.
- 1 in the Cybrex Beta system. It will only be revealed if the Contingency sterilizes 20% of the galaxy. A short time after the Contingency is defeated, the Cybrex will leave the galaxy, leaving the ringworld free for the taking.
- 1 in a random empty system if Utopia DLC is activated. It is completely ruined and each section requires repairing. If the Distant Stars DLC is activated as well the system can contain an unique anomaly.
- 3 in the systems of the Ancient Caretakers if Synthetic Dawn DLC is activated. The ringworld in the home system has 3 intact and one ruined section while the other two ringworlds are completely ruined and require each section to be repaired separately.