Precursors

Version

This article has been verified for the current PC version (2.8) of the game.

Exploration

Exploration

FTL

Anomaly

Precursors and Archaeology

Unique systems

L-Cluster

First League anomaly

The Precursors are long dead galactic empires predating even the fallen empires and the curators. Their ruins are scattered across the galaxy for the player to find via anomalies or archaeology sites. Precursor anomalies grant a special project which once investigated grants a small amount of Engineering, Physics or Society research as well as a precursor artifact. 6 artifacts are required to reveal the location of a precursor's home system.

If every precursor anomaly has been investigated but no empire managed to collect 6 artifacts a random event can trigger every 20 years and add another precursor anomaly on one of the previously investigated planets. The time is lowered to 13.3 years for Gestalt Consciousness empires.

AI empires can also sell a discovered artifact to Player empires for 1000 Energy. If the Player empire has the Warrior Culture civic it can threaten the AI empire to surrender it for free, the success rate depending entirely on both empires' Relative Power. Empires that hold a Protective, Friendly or Loyal attitude will offer the artifact for free instead of asking for payment. Each AI Empire will only offer an artifact once.

Once a Precursor homeworld has been discovered the empire will gain an artifact action to spend 50 Minor Artifacts to start a special project to delve into the secrets of one of the Precursor civilization. Finishing the special project will grant a permanent empire benefit. If the DLC is installed precursor anomalies will also grant 1-5 Minor Artifacts.

Precursor civilizations

There have been 7 precursor civilizations, 2 of them requiring the Ancient Relics DLC.

Precursor civilization	Homeworld	Homeworld reward	Home system deposits	Clues source	Secrets special project cost	Secrets special project rewards	DLC
Cybrex	Ruined Ring World	240-9999 Unity 350-2000 Engineering research 350-2000 Energy 10-30 Minor Artifacts Cybrex War Forge Relic Secrets of the Cybrex artifact action	None	Anomalies	12000 Engineering research	Mega-Engineering technology unlocked +10% Megastructure Build Speed Researcher gets Voidcraft expertise or 200 xp if already has it	None
First League	Fen Habbanis III	240-9999 Unity 350-2000 Society research 150-300 Influence 10-30 Minor Artifacts Secrets of the First League artifact action	10 of all research resources 10 Minerals 10 Energy	Anomalies	6000 Engineering research	+15% Industry Research Speed +10% Planet Build Speed Researcher gets Industry expertise or 200 xp if already has it	None
Irassian Concordat	Irassia	240-9999 Unity 350-2000 Physics research 350-2000 Minerals 10-30 Minor Artifacts Javorian Pox Sample Relic Secrets of the Irassians artifact action	10 of all research resources 5 Alloys 5 Exotic Gases	Anomalies	3000 Society research	+20% Biology Research Speed +5% Pop Growth Speed Researcher gets Biology expertise or 200 xp if already has it	None
Vultaum Star Assembly	Vultaumar Prime	240-9999 Unity 250-1500 Engineering research 250-1500 Physics research 250-1500 Society research 10-30 Minor Artifacts Vultaum Reality Perforator Relic Secrets of the Vultaum artifact action	10 of all research resources 10 Energy 5 Alloys 5 Exotic Gases	Anomalies	3000 Physics research	+15% Computing Research Speed +10% Amenities Researcher gets Computing expertise or 200 xp if already has it	None
Yuht Empire	Yuthaan Majoris	240-9999 Unity 350-2000 Energy 350-2000 Minerals 10-30 Minor Artifacts Yuht Cryo Core Relic Secrets of the Yuht artifact action	10 of all research resources 10 Minerals 10 Energy 5 Alloys 5 Exotic Gases	Anomalies	3000 Society research	Initiate Yuht Cleansing Process Decision Researcher gets New Worlds expertise or 200 xp if already has it	None
Baol	Grunur	The Last Baol Relic Secrets of the Baol artifact action	None	Archaeology sites	3000 Society research	Epigenetic Triggers technology -15% Terraforming Cost Researcher gets Biology expertise or 200 xp if already has it
Zroni	Zron Prime	Psionic Archive Relic Secrets of the Zroni artifact action	5 Zro	Archaeology sites	6000 Society research	+10% Psionics Research Speed Researcher gets Psionics expertise or 200 xp if already has it

Archaeological sites

Archaeology Site

Archaeological Sites are areas where remains of ancient civilizations have been preserved relatively intact. That can be discovered on survey, generated at game start or discovered a few years after a planet is colonized. Each time a planet is surveyed there is a 1.25% chance of an archaeology site being discovered.

A site can have 1-6 Chapters in addition to an introduction Chapter. Each Chapter has its own narrative and rewards and has to be unlocked before it becomes visible. Chapters are unlocked via Excavation. As long as an Archaeological Site is within an empire's borders that empire can task a Science Ship to excavate the site. The duration of an Excavation is determined by the Archaeological Site's Difficulty rating and can be reduced by -25% if the Scientist on the Science Ship has the Archaeologist trait. As the Scientist goes through excavations, it will generate a random number from 1 to 10 and add modifiers to the result, with the following formula: Result = dice roll + archaeology skill + clues − difficulty. Additional events can also trigger at the end of each excavation.

From Gateway Sent

The From Gateway Sent Archaeological Site is discovered by investigating the special project created by the Galactic Doorstep Origin.

Stage	1	2	3	4
Rewards	1-5 Minor Artifacts	1-5 Minor Artifacts	1-5 Minor Artifacts 90-250 Physics Research	1-5 Minor Artifacts 120-350 Engineering Research

On the Shoulders of Giants sites

The On the Shoulders of Giants Origin adds a lengthy Archaeological Site chain in the empire home system. The narration of the last two chapters of the final site are random but the rewards are always the same.

Site	Chapter 1 rewards	Chapter 2 rewards	Chapter 3 rewards	Chapter 4 rewards
Ex Gravitas	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	100-500 Minerals Something Waiting site location
Something Waiting	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts Random Technology Buried Deep site location
Buried Deep	1-5 Minor artifacts	1-5 Minor artifacts Random Technology In Memoriam site location
In Memoriam	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts Random Technology The Last Stand site location
The Last Stand	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts Random Technology	1-5 Minor artifacts Dark Secret site location
Dark Secret	1-5 Minor artifacts	1-5 Minor artifacts 350-2000 Minerals 250-1500 Alloys 250-1500 Exotic Gases	1-5 Minor artifacts	1-5 Minor artifacts Spurred by the Past empire modifier Once the Mid-Game year is reached an event chain will trigger

Ancient Relics sites

All other Archaeological Sites in the game require the Ancient Relics DLC to be found.

Site	Chapter 1 rewards	Chapter 2 rewards	Chapter 3 rewards	Chapter 4 rewards	Chapter 5 rewards	Chapter 6 rewards	Requirements
Ancient Battle Site	None	Random Technology 300-1000 Research 6-10 Minor artifacts					Uninhabitable planet
Strange Asteroid	None	Random Tier 2 Technology 6-10 Minor artifacts					Asteroid
Moon Bump	1-5 Minor artifacts	One of the following: Eco-Integration Studies tech Anti-Gravity Engineering tech 500 alloys					Uninhabitable planet
Trench World	1-5 Minor artifacts	Combat Training technology Modern Trench War modifier					Barren
Beautiful Bubble	1-5 Minor artifacts	1-5 Minor artifacts	150-500 Society research Rarely instead grants Anthem of Aurora				Uninhabitable planet
Beneath the Waves	1-5 Minor artifacts	1-5 Minor artifacts	Random New Worlds Technology unlocked 150-500 Society research if all techs are researched				Ocean
Get to the Bottom	1-5 Minor artifacts	1-5 Minor artifacts	Random New Worlds Technology unlocked 150-500 Society research if all techs are researched				Ocean
City of Bones	5 Minor artifacts	5 Minor artifacts	150-500 Society research Deploy Tissue Growth Stimulants decision Construct Fungiform Housing Units decision				Dry planet
Déjà Vu Dig	1-5 Minor artifacts	1-5 Minor artifacts	Random Technology				Uninhabitable planet
Hole in the Ground	1-5 Minor artifacts	1-5 Minor artifacts	Random Technology				Uninhabitable planet
Strange Flows	1-5 Minor artifacts	1-5 Minor artifacts	Random Technology				Molten
Too Angled	1-5 Minor artifacts	1-5 Minor artifacts	Random Technology				Uninhabitable planet
Dotted Archipelago	1-5 Minor artifacts	1-5 Minor artifacts	Random Society Technology				Ocean
Get Inside	1-5 Minor artifacts	1-5 Minor artifacts	Random Society Technology				Uninhabitable planet
Frozen Complex	1-5 Minor artifacts	1-5 Minor artifacts	Plasma Accelerators technology 120-350 Society research if already researched				Frozen
Subterranean Hollows	1-5 Minor artifacts	1-5 Minor artifacts	Hostile Environment Adaptation technology 500 Society if already researched				Habitable planet
Mutant Fossils	5 Minor artifacts	5 Minor artifacts	Mutation Vats Planetary Feature				Tomb
Robot Debris	1-5 Minor artifacts	1-5 Minor artifacts	6-10 Minor artifacts 300-1000 Engineering research				Asteroid
Target from Orbit	1-5 Minor artifacts	1-5 Minor artifacts	150-500 research				Uninhabitable planet
Any Other Rock	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	Permanent +5% Unity modifier			Molten
Anyone Home?	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	Random Society Technology			Uninhabitable planet
Asteroid Blast Door	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	50-100 Minor artifacts			Asteroid
Gas Giant Structure	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	6-10 Minor artifacts 4000 Energy			Gas Giant
Relic Rails	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	6-10 Minor artifacts Research modifier for 15 years			Housing building
The Echoes Inside	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	150-500 Society research			Barren
The Endless Expanse	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	10-30 Minor artifacts			Frozen
Fossilized Remains	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	10-30 Minor artifacts Blade of the Huntress Relic		Colony
Kleptomaniac Rats	6-10 Minor artifacts	6-10 Minor artifacts	6-10 Minor artifacts	6-10 Minor artifacts	10-30 Minor artifacts Shard guardian awakens		Relic
Message in the Dust	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts 1 Corvette		Habitable planet
Whispers in the Stone	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	10-30 Minor artifacts 500 Rare Crystals Lithoid Crystal Plants		Mining District
Ancient Tomb	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	10-30 Minor artifacts Head of Zarqlan Relic	Mid-Game Uninhabitable planet Holy Guardians exist
Crashed Starship	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	10-30 Minor artifacts	Uninhabitable planet
The Grand Herald	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts	1-5 Minor artifacts Titan (25-75% damaged)	Dry planet

Precursor sites

Precursor Archaeology Sites are visible only to the empire that starts the event chain and are used to advance the Baol and Zroni event chains. When a Zroni Archaeology Site is discovered the planet will gain a deposit of 2-4 Zro.

Precursor	Site	Chapter 1 rewards	Chapter 2 rewards	Chapter 3 rewards	Chapter 4 rewards	Chapter 5 rewards
Baol	Grunur Ruins	5 Minor artifacts	5 Minor artifacts The Barren site location
	The Barren	5 Minor artifacts	5 Minor artifacts	5 Minor artifacts The Shattered site location
	The Shattered	5 Minor artifacts	5 Minor artifacts	5 Minor artifacts	5 Minor artifacts The Silenced site location
	The Silenced	5 Minor artifacts	6-10 Minor artifacts Grunur system location
Zroni	Abandoned Colony Ruins	1-5 Minor artifacts	1-5 Minor artifacts 90-250 Physics research	1-5 Minor artifacts 150-500 Society research Psionic Theory technology unlocked if not Gestalt Consciousness Zroni Minor Colony site location
	Zroni Minor Colony	1-5 Minor artifacts 90-250 Society research	1-5 Minor artifacts Zroni Minor Colony site location
	Zroni Minor Colony	1-5 Minor artifacts	1-5 Minor artifacts Zroni Minor Colony site location
	Zroni Minor Colony	1-5 Minor artifacts	1-5 Minor artifacts Zroni Major Colony site location
	Zroni Major Colony	60-150 Engineering research 90-250 Society research	1-5 Minor artifacts 90-250 Society research	6-10 Minor artifacts Zron system location
	Zron	1-5 Minor artifacts 2 Zro	1-5 Minor artifacts 90-250 Society research	1-5 Minor artifacts 90-250 Society research	1-5 Minor artifacts 120-350 Society research 5 Zro	10-30 Minor artifacts Psionic Archive relic

The Sentinels

The Sentinels is an Archaeology Site with slightly different mechanics. It can be discovered after a planet is colonized and unlike all others it brings a choice when completely excavated. When discovered it adds an Archaeological Site blocker to the colony.

	Chapter 1	Chapter 2	Chapter 3
Difficulty	2	2	3
Rewards	1-5 Minor Artifacts	1-5 Minor Artifacts	1-5 Minor Artifacts Archaeological Site blocker removed

When the site is completely excavated the empire will get the following choices:

• If not Xenophobe or Fanatic Xenophobe gain an Unity from Jobs planet modifier and a permanent blocker.
• If not Xenophobe or Fanatic Xenophobe issue a special project to open the Sentinels. When the special project is complete the empire will have the option the hear the Sentinels or attack. Attacking will have the Sentinels invade the colony with 9 armies. Hearing them out will bring the option to either gain a permanent blocker and 9 defense armies or be hostile and have the Sentinels invade the colony with 9 armies. The invasion has an Army Strength of roughly 2400.
• Issue a special project to destroy the Sentinels. When the special project is complete the will be invaded by 9 armies. If the armies are defeated the colony will gain the Sentinels planetary feature and empire will be offered to either gain 150 Influence or issue a special project to see what the Sentinels were guarding. Finishing the special project will bring the following options:
  • Gain 300 Influence and the Cheap Thrills planet modifier that gives -10% PoP Consumer Goods Upkeep and a +5% Happiness.
  • Gain the The Evermore planet modifier that gives +10% Research.
  • Gain access to the Replicate the Evermore special project.
  • If Militarist or Xenophobe gain 300 Influence and access to Cheap Thrills planet modifier that gives +10% Militarist Ethics Attraction, +10% Xenophobe Ethics Attraction, -10% Consumer Goods Upkeep and +5% Happiness.

Excavation events

If at the end of an Excavation phase the result is not high enough to grant a Clue or finish the Chapter then one of the following events may happen:

• Science Ship Scientist dies, -2 Clues
• Archaeology team members die, -1 Clues
• A dangerous situation is avoided, +3 Clues
• Choice to pay 100 Energy to get +3 Clues or do nothing and get -2 Clues
• Science Ship Scientist gains the Maimed trait

Excavation Time

Assuming you never get any of the aforementioned events, the average number of rolls required to complete the chapter can be read from this table. "S + C - D" is the scientist's archeology skill, plus clues, minus difficulty. A level 3 scientist with Curator Archaeology Lab tech researched and 2 clues, excavating a level 4 chapter, would have an S + C - D of 5 + 2 - 4 = 3, and will need slightly under four and a half more rolls, on average, to complete the chapter.

S + C - D	Expected Rolls
-4	29.85
-3	19.85
-2	14.85
-1	11.51
0	9.01
1	7.01
2	5.54
3	4.40
4	3.39
5	2.73
6	2.29
7	1.96
8	1.70
9	1.49
10	1.33
11	1.2
12	1.1
13	1
14	1