Subterranean Civilization

Version

Please help with verifying or updating older sections of this article. At least some were last verified for version 3.8.

This article is for the PC version of Stellaris only.

Event chains

Events

Empire event chains

Habitable Worlds Survey

Comet Sighted

Fleet Maneuvers

Horizon Signal

Mass Extinction Through the Ages

Radical Cult

Sublight Exploration Probes

Wanderlust: Rogue Scientist

The Hunt for the Hyacinth

 Fountain of Youth

 Genetic Crossroads

 On the Shoulders of Giants

 Homesick

 The Cost of Freedom

 The Fear of the Dark

 The Guest

Anomaly event chains

Drifting Battlefield

Gas Giant Signal

Impossible Organism

Limbo

Orbital Speed Demon

Shrines to the Old Gods

The Ransomeers

 42 Years and 3 Days

 Lost Amoeba

Colony event chains

A New Species

Abandoned Terraforming Equipment

Ancient Drones

Dancing Plague

Feral Overload

Hidden Vault

Impossible Corrie

Metallic Puddles

Mharin Kharin

Migrating Forests

Mushroom Picking

Myrmeku Activity

Nemma World

Rise of the Manifesti

**Subterranean Civilization**

The Doorway

Underground Vault

Unexpected Mineral Seams

Primitive civilization event chains

Anti-Alien Task Force

Missing Scientist

Rogue Agent

Shuttle Crash

 Propulsion Proponent Proclamation

Subterranean Civilization is a colony event chain that has a very small chance to trigger 2 or 3 years after any colony has been founded. It can only happen once per game. The event chain offers two mutually exclusive paths which both have eventual rewards and drawbacks. The hostile path can also be followed should peace fail.

### Seismic Disturbances

 *There have been many reports of unexplainable seismic disturbances on [colony name]. Tremors can be felt across the [planet or moon], and many of our settlements have suffered damage. While investigating the earthquakes, our scientists discovered a vast network of subterranean caverns.

The deepest of these caverns are home to some kind of indigenous civilization, and they appear to be tunneling towards the surface! Ground vibrations from our settlements may have triggered this behavior, but we cannot be certain. There is no telling how these aliens will react when they spill out of their tunnels and encounter our colonists!*

* Colony is not on a Ringworld, Habitat, Ecumenopolis, Relic or Tomb World

* Issue Special Project: Establish Communications
* Issue Special Project: Preemptive Strike

* Issue Special Project: Preemptive Strike

### Message Delivered

 *Trade with the subterranean aliens on [colony name] has dried up as of late, with their caravans showing up more and more seldom. Today we received a message from a representative of their military. They don't seem very pleased.*

* Relations with the subterranean civilization have been harmed twice

**Let's see it.*** **Subterranean Civilization** modifier removed
* Removes the  Subterranean Contact Zone planetary feature

### Subterranean Invasion!

 *The subterranean aliens on [colony name] have emerged on the surface! Large armies equipped with primitive yet lethal projectile weapons are spilling from the tunnels, and their vanguard has already begun an assault on our settlements.

Our security forces are responding, but we may need to send reinforcements!*

* 6-12 industrial armies invade the colony

Victory

*Our forces have managed to drive the subterranean aliens on [colony name] back into their underground lairs, and they are contained for the moment. This is a temporary solution, however, and it is only a matter of time before they break out onto the surface again.We need to strike at them below ground, and our strategists have devised a new attack plan. It has been added to the Situation Log.*

**We need to solve this problem for good.*** Issue Special Project: Destroy Subterranean Civilization

Defeat

*Our forces have been decimated on [colony name], and the subterranean aliens have taken full control over all of our settlements! They are using one of our own satellites to send a message to us.*

* A random  Fanatic Militarist and  Authoritarian empire is created and takes control of the starbase and all planets in the former colony system.