|Available only with the Utopia DLC enabled.|
Megastructures are colossal object constructions. Expensive and time-consuming, these remarkable feats of engineering are nonetheless important wonders that provide large bonuses, demonstrating the technological and economical primacy of the builders' empire.
It is possible to find ruined megastructures spread in the galaxy to repair and restore them into their final form. Doing so allows saving a lot of the resources required to construct them. While restoring the megatructures does not require any ascension perks, it does require the player having researched the technology Mega Engineering.
It is only possible to build, upgrade, or restore one megastructure at a time, except in the case of habitats. In general, megastructures cannot be destroyed - the only exception to this are Habitats which can be destroyed with war demands or via certain events.
A number of Ascension Perks enable or affect the building of Megastructures.
This Perk enables the building of Habitats. It has significantly lower requirements than the perk for the other Megastructures, requiring only some of the prerequisites of Mega Engineering rather than the tech itself.
Circle of Life
Requires Mega Engineering and Voidborne. This enables the construction of Ringworlds. They offer extreme living space at higher efficiency than Habitats. However the system they are built in must be devoid of habitable planets as in the construction of the ringworld all planets will be destroyed to supply the materials. You can build an infinite number of these.
Requires Mega Engineering. Enables the Dyson Sphere, Science Nexus and Sentry Array. What each of these Megastructures have in common is that they provide effects and bonuses without any of the disadvantages associated with a colonized planet.
An artificial planet in all but name, these Habitats offer 12 tiles to work coupled with 100% habitability for all species. Its graphical model is dependent on the builders' species type. Note that the constructed habitat still requires colonization.
It has the peculiarity of having a unique set of buildings distinct from normal planetary ones. This set of buildings has good Energy and research yields, but is less effective for generating Food and Minerals. Several event or tradition-unlocked buildings can also be constructed, e.g. Spiral-Feed Power Hubs and Paradise Domes.
Habitats have considerable production penalties for both Minerals and Unity, as they effectively act as a rather small planet. However, they offer superior Energy and Science income, while doubling as an Orbital Farm. They also require considerably less micromanagement, because none of the buildings need upgrades nor provide adjacency bonuses. Of all the megastructures, they have the least onerous requirements in terms of technology and placement.
Habitats are uninhabited when they are built; they need to be colonized afterwards. They will also inherit orbital tile deposits from their orbiting planet.
Habitats are normally indestructible because they are treated as planets, however they can be disassembled by war demand. If a habitat is destroyed, it will strangely never be possible to build another habitat, or even a mining/research station, orbiting the planet, so any strategic resource on the planet is permanently lost. What's more, habitats can't have spaceports, so if an empire has only habitats and no planets, it will never be able to build ships.
Immense in both radius and scope, these Ringworlds encircle their system's sun and award their owner four, 25 tile sized sections when fully constructed. Its carefully designed ecosystem and finely-tuned atmosphere imply excellent living conditions towards all higher forms of life; that is to say, all residing species have 100% habitability on a ringworld.
The initial site is built by a construction ship around the star, and cannot be begun if another construction ship is building a megastructure. Once the site is complete, it constructs the subsequent sections without the need for a construction ship.
Ringworlds cannot be built around black holes. All planets in the system are consumed upon the completion of one of its four sections.
|100px||Site||-5||1 800|| 300 |
|100px||Frame||None||4 800||20 000|
|Completed Section||None||3 600||20 000|
The Ringworld offers a massive amount of living space (100) while only counting as 4 Planets. The big limitation is that there are only very few Systems one can build them in, as the system requirements are identical to the ones for a Dyson Sphere, except it also needs a lot of planets to be used for raw material. Like Habitats it also requires a separate Ascension Perk from the other Megastructures. It is the only Megastructure that is exclusive for its system, as its creation will consume all other stellar bodies in the system.
Sometimes there is an event while constructing a section of the Ring World that grants you a temporary +20% Megastructures build speed. There is also an opportunity to gain 500 minerals in exchange for increase of Ring Section building time by 20 days. You may also gain an event while it is still under construction where a neighboring empire will request to inspect the ring world for fears of "weapons of mass destruction", delaying it, or if refused giving an opinion penalty to you by -40, which decreases by +2 yearly. You may also gain an event while it is under construction where an empire will have a vision and wish to bless the ringworld, refusing does nothing, while accepting delays the building by 20 days and grants an opinion bonus. There is also an event where one of the planets had been home to a type of giant space worm, which the workers on the ringworld grow to like. You can either exterminate the worm species, halting construction for a month, or continue with the worms. If you chose to continue with the worms, a few days later the worms are found to be larvae, and to be feeding on the bodies of several missing workers. You must then kill off the worms, halting construction for a month.
These multi-staged, truncated icosahedron-shaped structures harness the energy output of an entire star. A fully constructed Dyson Sphere provides a whopping +400 energy.
All rocky planets and moons in the system turn into frozen or cold barren worlds upon its completion. This is meant to represent the lack of thermal radiation they would receive considering the star has been mostly completely encased.
|Site||None||-5||1 800|| 300 |
|Frame||None||None||3 600||40 000|
|Partial (25%)||+100||None||3 600||40 000|
|Partial (50%)||+200||None||3 600||40 000|
|Partial (75%)||+300||None||3 600||40 000|
|Dyson Sphere||+400||None||3 600||40 000|
During the construction of the framework of the sphere, neighboring empires may tell you their astonishment about your progress in constructing the sphere and request for your permission to allow a group of engineers to study the technology. Accepting the request may result in opinion improvement by 40 which decreases by -2 yearly. You will also be awarded 250 points of engineering research. There is no clue that whether the empire will be able to construct Dyson Spheres after the event.
Once you finish the framework of the Sphere, there is a chance where a neighboring empire will approach you asking you to deconstruct the Sphere due to the importance of that star in said empires culture. Refusing to dismantle the Sphere adds "The Blind Wanderer" to their opinion screen which reduces their opinion of you by -40 which decreases by +2 yearly.
The Dyson Sphere offers considerable energy income at no cost for Unity or Research from population/colonized planets. Habitats may also be built in systems with a Dyson sphere, but not other megastructures.
It is possible to build a single Science Nexus in each (non-black hole) system within your empire's borders.
The Science Nexus provides a huge bonus to Science without any penalty from having another colonized planet. The initial site cost 10,000 minerals, and the three stages after cost 20,000 minerals each while providing 30/60/90 to all science. This is equivalent to a fairly good research-focused planet, although fully-focused size-25 planets can output over 90.
Upon completion, you may randomly get an event where you may sacrifice one of your scientists to increase the science yield to 100 to all science, up from 90.
The completely finished Sentry Array will give you vision over the entire galaxy. This can make it an important military and strategic asset, as complete intelligence of every pop and fleet in the galaxy can give considerable strategic information. On lower levels it will still provide at least considerable vision, quickly eliminating any "blind spots" in the sensor coverage of the player or their alliance.
Provided you do not lose the system hosting your Sentry Array, it makes the Planetary Signal Booster technology useless, allowing you to focus on other late-game repeatable technologies.