Stellaris 4.5.2 megastructures

37 megastructures in the files of Stellaris 4.5.2: 26 that an empire builds after a technology, the rest special ones (behemoth eggs, arkships, habitats, crisis structures, ruins). Each page lists every stage with its cost, build time, upkeep and output, and where it may be built in the game's own words.

Megastructures you research and build

Ring World

4 stages · 340 months · Ring Segment

Must be built in a system with no habitable planets or habitats.

Dyson Sphere

6 stages · 55 years · Dyson Sphere

Must be built in a system with a single star and no habitable planets.

Sentry Array

5 stages · 25 years · Sentry Array

Each empire can only build one Megastructure.

Science Nexus

5 stages · 12620 days · Science Nexus

Each empire can only build one Megastructure.

Gateway

2 stages · 8 years · Gateway Construction

Must be built outside a system's gravity well.

Matter Decompressor

5 stages · 45 years · Matter Decompressor

Must be built in a system with a black hole and no habitable planets.

Strategic Coordination Center

4 stages · 35 years · Strategic Coordination Center

Each empire can only build one Megastructure.

Mega Art Installation

5 stages · 45 years · Mega Art Installation

Each empire can only build one Megastructure.

Interstellar Assembly

5 stages · 25 years · Interstellar Assembly

Each empire can only build one Megastructure.

Mega Shipyard

4 stages · 20 years · Mega Shipyard

Each empire can only build one Megastructure.

Quantum Catapult

4 stages · 20 years · Quantum Catapult

Must be built on a Neutron Star or Pulsar.

Hyper Relay

One stage · 1 year · Hyper Relays

Must be built outside a system's gravity well.

Orbital Ring

One stage · 2 years · Orbital Rings

Must be built around a colonized planet.

Horizon Needle

One stage · 160 months · Nascent Universes

Each empire can only build one Megastructure, in orbit of their Capital.

Synaptic Lathe

One stage · 80 months · Scalable Reservoir Computing

Each empire can only build one Megastructure.

Arc Furnace: Equatorial Band

4 stages · 10 years · Arc Furnace

Dyson Swarm: Array

3 stages · 9 years · Dyson Swarm

Must be built in a system with a single star.

Deep Space Citadel

One stage · 3 years · Deep Space Citadel

Grand Archive

One stage · 5 years · Galactic Archivism

Shroud Seal

One stage · 5 years · Psionic Suppression

Arkship (Civilian)

One stage · 2 years · Arkship Construction

Arkship (Scientific)

One stage · 2 years · Arkship Construction

Arkship (Military)

One stage · 2 years · Arkship Construction

Waystation

One stage · 6 months · Waystations

Stellar Cannon

4 stages · 20 years · Stellar Cannon

Must be built on a Neutron Star or Pulsar.

Habitat Central Complex

One stage · 5 years · Orbital Habitats

Must be built in orbit of a major planetary body.

Special megastructures

Megastructures that come from events, origins, crises or other megastructures rather than a technology.

Ruined Aetherophasic Engine Frame

Behemoth Chrysalis (base)

2 stages · 1081 days

Behemoth Chrysalis (big)

One stage · 30 months

Minor Orbital

One stage · 30 months

L-Gate

One stage

Megastructures: questions

How do you build megastructures in Stellaris?

Research the megastructure's technology, then a construction ship starts its first stage where the game allows it; each later stage is an upgrade with its own cost and build time. Each page lists them.

Which megastructures are there?

Ring World, Dyson Sphere, Sentry Array, Science Nexus, Gateway, Matter Decompressor, Strategic Coordination Center, Mega Art Installation, Interstellar Assembly, Mega Shipyard, Quantum Catapult, Hyper Relay, Orbital Ring, Horizon Needle, Synaptic Lathe, Arc Furnace: Equatorial Band, Dyson Swarm: Array, Deep Space Citadel, Grand Archive, Shroud Seal, Arkship (Civilian), Arkship (Scientific), Arkship (Military), Waystation, Stellar Cannon, Habitat Central Complex.

Source: common/megastructures, Stellaris Cygnus v4.5.2 (9776).