Unique systems can only spawn once per galaxy and have a unique event or anomaly related to them. Unique systems in the base game are rare while those added by DLCs have a higher chance to appear.
Unique systems have their spawn chanced determined by the galaxy size. They will never appear in hyperlane choke points. The percentages for each unique system to appear are the following:
If none of the starting empires have Sol as their home system there's a 50% chance that it will spawn in the galaxy, Earth being found in one of the following states:
- Crusader Kings Age
- Humans are Authoritarian, Spiritualist and Xenophobe and have primitive armies made up of feudal levies.
- Hearts of Iron Age
- Humans are Materialist and Fanatic Militarist, and have the industrial armies of Nazi Germany, USSR, the US, UK and Imperial Japan. In Ironman mode successfully invading at this time will unlock the Outside Context achievement. If they advance to Atomic Age they might start a nuclear war.
- Present Day
- Humans are Xenophile and Fanatic Egalitarian, and have the post-atomic armies of the US, China, Russia and the European Union. ISS II orbits Earth. If they discover FTL they will become the United Nations of Earth. They cannot start a nuclear war at this stage.
- Nuclear Wasteland
- Humanity has wiped itself out in a nuclear war and Earth is a tomb world. The planet has a unique level I anomaly which when investigated will reveal a species of pre-sentient cockroaches that have the Tomb World climate preference and Adaptable trait.
Sanctuary is a system containing an abandoned ring world of previous Enigmatic Observers. Originally created to act as a nature preserve and house primitive life, the system was abandoned but left guarded by multiple defense platforms of approximately 42k fleet power. Upon discovering the system an empire is contacted by the automated defense facility, which explains the history and purpose of the facility. Every message ends in "Do not approach this facility under any circumstances" and indeed the defenses will fire upon any ship that approaches it.
The Sanctuary defenses contain the following stations:
|1 Sanctuary Core
||4 A-1 Fortresses||11 A-2 Outposts|
Despite having no engine modules, stations are, in fact, mobile, and therefore cannot be engaged with artillery ships from a safe distance, one by one. Defeating them may prove a challenge but destroyed platforms are not rebuilt, allowing the system to slowly be overtaken.
The ring world is almost completely intact and each habitable segment houses a randomized pre-FTL species, none of them advanced beyond the Steam Age. Any empire that manages to defeat the platforms can lay claim to the extremely valuable system and decide the fate of the inhabiting species. It should be noted that since the species have evolved and reached sentience on the ring world they have the Ring World climate preference which hampers their ability to colonize without compensatory methods.
A rare special system contains Zanaam, a size 25 Gaia world with the unique Valley of Zanaam Planetary Feature, the system is guarded by a strong fleet of 11k fleet power, which can drag out taking the system. Aside from the eponymous planet, the System has 3 broken worlds, an asteroid ring and 6 shipwrecks. The planets can have random anomalies as usual.
The Fleet guarding it consists of 24 Guardian Class Destroyers, named from Alpha to Omega, which look like Ancient Mining Drones but use far more advanced components.
Upon entering the System, the player is given a message stating they will be destroyed. The Fleet is hostile, however it is not set to aggressive stance, simply blocking any approach to the planet. After they are defeated the planet can be colonized as usual.
A random system in the galaxy will contain an asteroid field where one of the large asteroids is orbited by an Ancient Manufactory identical to the Mining Drone stations. Surveying the asteroid will reveal a level III anomaly. Investigating it will bring the option to either:
- Leave the manufactory alone. Xenophobe and Fanatic Xenophobe empires will gain 100 Influence from this option.
- Start a Special Project to restore the manufactory with a fleet. Not available to Fanatic Xenophobe empires. Possible outcomes are granting the Rare Crystals Manufacturing technology, launching the manufactory into the star and awakening 3 hostile Ancient Mining Drones or Crystalline Entities. If the system has been claimed another possible outcome is turning the manufactory into a mining station and adding a deposit of 10 Minerals to the star.
Distant Stars systems
|Available only with the Distant Stars DLC enabled.|
Twin Tomb World Civilizations
This star system contains two Tomb Worlds, both with humanoid Bronze Age civilizations. Surveying the second Tomb World will reveal a level III anomaly. Investigating it will grant a moderate amount of Society research. The species are always the following:
This system will not spawn if primitives have been disabled.
One anomaly in the galaxy might be called The Vechtar Zavonia when successfully investigated, describing a planet called Paridayda and a species called Mardak Vol. Choosing the option to search for the planet will start a special project. Finishing it will create a neighbor system and point to a Barren World inside. Choosing to investigate further when entering the system will start a special project to investigate the planet with a science ship. Finishing the special project takes 60 days and will reveal the planet as a size 25 Gaia World with the Stone Age Mardak Vol civilization.
A few days after the system has been claimed a species called the Vol will arrive with a fleet to purge the Mardak Vol. Accepting will destroy the civilization and add a removable blocker to the planet. Refusing will have the fleet attack the system. If their fleet is not defeated they will bombard the planet with the Armageddon stance. Once all Mardak Vol pops are killed by bombardment all tiles on the planet will get 4 removable blockers.
Accepting is the recommended course of action as not only does it avoid the fight but the Mardak Vol would take a long time to enlighten or remove Stellar Culture Shock and have the Gaia World climate preference. In addition if the planet is colonized the colonists will gain +10% Happiness for 10 years.
Paridayda has a unique planet modifier granting it the following:
A random pulsar system in the galaxy might contain a Tomb World planet called Ruinous Core orbited by a Tomb World moon called Lost Encampment, as well as various debris throughout the system. A similar nearby system will contain three Tomb Worlds: Silent Colony, Decayed Hub and Crumbling Borough. A second nearby system will contain a Tomb World called Fallen Outpost. Unlike other Distant Stars systems, these systems will give a notification when one is entered for the first time. Surveying Ruinous Core will reveal a level II anomaly. Investigating it will grant a significant amount of Society research.
A few decades after the first system has been entered a species called Ketling will emerge in any of the three systems that haven't been claimed by an empire. A special project will be added to investigate any Tomb World in one of those systems and doing so will grant a large amount of Society research.
Planets with Ketlings cannot be colonized but can be invaded. If invaded they will suffer a 5 years Culture Shock identical to invading an Early Space Age civilization.
Another few decades after the Ketling have emerged they will become the following Federation Builders empire:
|Ketling Star Pack|
All their planets will be filled with buildings and they will get 10 armies and a fleet of 8 cruisers, 8 destroyers and 10 corvettes.
Abandoned Observation Post: This class F star system contains an Abandoned Observation Post orbiting a habitable world. Surveying the planet will reveal a level IV anomaly. Investigating it will bring the option to either:
- Investigate the observation post with a science ship to gain a moderate amount of Society research.
- Leave the observation post alone for 50 Influence.
Abandoned Star Platform: This system contains an Abandoned Star Platform orbiting a pulsar star. Surveying the star will reveal a level IV anomaly. Investigating it will bring the option to start a 60 days special project to either:
- Repair the platform with a construction ship to add a 6 Energy deposit to the pulsar.
- Salvage the platform with a science ship to gain 20% to the next level of lasers technology.
Shielded World: This class B star system contains a Shielded World. Surveying the planet will reveal a level IV anomaly. Investigating it will bring the option to either:
- Repair the shield with a science ship to add a 8 Physics and 4 Society deposit to the world for a few decades.
- Interrupt the time loop with a science ship, gaining a small amount of Physics research. There is a 50% chance of the world turning into a tomb world and a 50% chance of creating a Fanatical Purifier Prikki empire.
- Leave the planet alone and gain a small amount of Physics and Society research. Around a decade later a Fanatical Purifier Prikki empire will emerge.
The Veil This binary star system contains a planet that will appear either as a Gaia World or a Shrouded World. Surveying it will reveal the Phase-Shifted planet modifier (-50% Planet Build Speed) and the only level X anomaly besides certain precursor anomalies in the game. Investigating it will describe how every 3 months the planet shifts between a Gaia World and a Shrouded World and grant a moderate amount of Physics. Once the system has been claimed you will be given the option to either:
- Leave the planet for a moderate amount of Influence.
- Start a special project to use a science ship to freeze the phase-shift. The project takes 180 days and finishing it permanently sets the planet to a Gaia World. It will also grant a moderate amount of Physics research.
Rudimentary Robots: This star system contains a single habitable world with the Metal Boneyards planetary feature among other uninhabitable planets. Surveying the planet will reveal a level I anomaly. Investigating it will add 3 or 4 robot Pops on the planet. After the planet is colonized you will be given the option to either:
- Dismantle the robot Pops and gain 100 Minerals.
- Keep using the robots. 90 days later a special project to investigate the robots with a science ship is given. Finishing the special project takes 30 days and gives a large amount of Society research.
Regardless of the chosen option, around 5 years after the planet has been colonized a number of colonists will gain the Erratic Behavior modifier, giving -25% to Happiness, Governing Ethics Attraction and Resource Production, and a special project to investigate it will be added, costing 60 Society research. Finishing the research project grants a random Biology technology. If the special project is not completed in 4 months three enraged colonists armies will form and attempt to occupy the planet.
Sea of Consciousness: This class A star system contains a size 24 Ocean World among other uninhabitable planets. Surveying the planet will reveal a level II anomaly. Investigating it will give the planet a deposit of 5 Society. If the empire is not a Machine Intelligence it will also grant a moderate amount of Society research and start a special project to build a research station over the planet. 6 months later you will get three options:
- Allow the scientist Leader to leave. One year later it will bring a large reward of Physics and Society research as well as a random psionic technology.
- Disallow the scientist Leader to leave. 3 months later the Leader will send a message and die 10 days afterwards.
- Remove the scientist Leader, ending the event chain.
Caretaker Escape Pod: This binary star system has as its last planet a Gas Giant with escape pods in orbit. Surveying the planet will reveal a level III anomaly. Investigating it will bring the option to either ignore the pod for a small amount of Influence or hail it and get the following options:
- Valid if AI is not outlawed: Accept Caretaker AX7-b as a leader, gaining a level 4 governor Leader.
- Valid if AI is not outlawed: Examine Caretaker AX7-b for a moderate amount of Engineering research.
- Valid if AI is outlawed: Destroy the pod for a small amount of Influence.
- Valid if Machine Intelligence: Recycle Caretaker AX7-b for a small amount of Minerals and Engineering research.
Superflares: This class G star system contains a number of uninhabitable planets and a gas giant with multiple moons, one of them being a Tomb World with the unique Irradiated Valley planetary feature. Another one of the planets is a frozen world with a level I anomaly. Investigating it will add a 4 Society deposit to the world. The star also has a 3 Physics deposit instead of a regular Energy one. A year after the planet is colonized a special project will be added to shield the colony with a science ship. The project takes 30 days to complete and gives the planet a +10% Unity from Jobs modifier. The scientist will also gain the Expertise: Field Manipulation trait. If the project is not started in 150 days one pop will die and the planet will get -10% Habitability and -15% Energy from Jobs for 20 years.
Gaia Civilization: This class M star system contains a Gaia moon orbited by a derelict station. Surveying the moon will reveal a Stone Age molluscoid civilization as well as a level VI anomaly. Investigating it will grant a significant amount of Physics and Society research. The primitive civilization has the Gaia World climate preference, as well as the Extremely Adaptive, Slow Breeders and Sedentary traits.
Ancient Relics systems
|Available only with the Ancient Relics DLC enabled.|
Shielded Relic system
A random binary system in the galaxy will always contain a size 25 Shielded World guarded by a fleet of 5k fleet power with ships identical to the ones guarding Zanaam. Surveying either the Shielded World or its moon will reveal the unique Archaeology Site that can be excavated.
A class M system in the galaxy will always contain a Relic World. Surveying it will reveal the unique Ruined World Archaeology Site that can be excavated.
|Chapter 1||Chapter 2||Chapter 3||Chapter 4|
|Rewards||1-5 Minor Artifacts||None||1-5 Minor Artifacts|| 10-30 Minor Artifacts|
The Omnicodex Relic
A random binary system in the galaxy might contain a Relic World. Surveying it will reveal the Planetary Machinery Archaeology Site that can be excavated.
|Chapter 1||Chapter 2||Chapter 3||Chapter 4||Chapter 5||Chapter 6|
|Rewards||120-350 Society research|| 120-350 Society research
1-5 Minor artifacts
|2 Minor artifacts||1-5 Minor artifacts||1-5 Minor artifacts||120-350 Engineering research|
Finishing the excavation will open a dialogue window with C.A.R.E. Interactive Interface. Agreeing to help it will issue the Develop A Cure For The Ferrophage Special Project. Finishing it takes 10 years and grants the Defragmentor Relic while the Relic World gains a permanent +10% Energy from Jobs modifier. Refusing will grant 100 Influence instead.
- This system will not appear if the Apocalypse DLC is installed, Privateers being replaced by the Marauders.
A random class M star system in the galaxy will be home to the Privateers, a group of 3 pirate fleets. Those fleets are Young Blood (around 700 fleet power), Scarred Veterans (around 8k fleet power) and Old Guard, a huge pirate galleon with 12k fleet power, possessing 40k health and massive amounts of armor. The fleets use kinetic, energy and guided weapons, all of the lowest level. They lack any kind of point defense, making them easy targers for fleets armed with guided weapons or strike craft. However the system's only resources are two asteroids with slightly higher Minerals deposits.