Underground Vault

Version

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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

Underground Vault is a colony event chain that may happen 2 or 3 years after a Tomb World has been colonized. It can only happen once per game. The event chain has entirely random outcomes.

### Underground Vault

 *Geological surveys conducted by our colonists on [colony name] have revealed a massive vault buried deep inside a mountain range. All evidence points towards this being some kind of fallout shelter built by the same species that perished in the [planet or moon]'s ancient nuclear war.

The vault has been sealed for many centuries, but our instruments have detected a faint power signature emanating from within. Our scientists are eager to open the vault and discover what lies behind its reinforced doors.*

* Not  Gestalt Consciousness
* Planet was not turned into a Tomb World by orbital bombardment

**Let's crack this thing open!*** Issue Special Project: Open Underground Vault

Special Project Completed

*Our science expedition has finally managed to open the vault on [colony name], but they found nothing but ancient skeletal remains inside. It would seem that the vault's original inhabitants ran out of food approximately 200 years ago, at which point they turned on each other in some sort of cannibalistic frenzy. The scattered bones, many of them covered in gnaw marks, paint a grisly picture of the final moments that were experienced by the last survivors of this once proud civilization.On the bright side, the logs and data libraries inside the vault should be enough to keep our behavioral scientists and xeno psychologists busy for many years to come.*

* 33% chance

**Interesting.*** Adds an  Underground Vault planetary feature to the colony

Special Project Completed

*Our scientists finally managed to open the ancient vault on [colony name], only to unleash a flood of mutated horrors - the twisted remains of the original inhabitants.The creatures slaughtered the science team in a matter of seconds, and then fanned out into the countryside. Thousands of colonists have been butchered, with entire settlements falling to the ravenous horde. We have fortified our remaining cities and established defensive perimeters, but this may not be enough!*

* 33% chance

**Man the defenses!*** 3 armies invade the colony

Special Project Completed

*The great vault on [colony name] has been unsealed. To the surprise of our scientists, the vast complex behind the massive vault doors housed millions of survivors from the ancient nuclear war that once ravaged this world. Despite their limited resources, they have managed to maintain a self-sufficient society for centuries. They were wary of our scientists at first, having never encountered aliens before, but also deeply grateful for our help in opening the vault.The vault contains large stores of equipment and machinery that was specifically designed for rebuilding civilization after a nuclear holocaust. It can only be operated by these aliens, but they seem more than willing to join your colonists on the surface once they have adapted to natural sunlight again.*

* 33% chance

**Let us rebuild this world together.*** Adds an  Underground Vault planetary feature to the colony
* Adds 3 pops from a random species to the colony
	+ If the event chain started on Earth the pops will be human

 **Excellent. Prepare the slave collars!*** Adds an  Underground Vault planetary feature to the colony
* Adds 3 pops from a random species to the colony with the **Slaves** citizenship
	+ If the event chain started on Earth the pops will be human

### Mutants Overrun [colony name]

 *Our main forces on [colony name] have been decimated by the onslaught of the mutated creatures! The vile beasts are now roaming free across the entire colony, butchering our colonists with impunity. There are reports of survivors having fled the settlements to hide in the countryside, but it's only a matter of time before they are found by the marauding creatures.*

### The Liberation of [colony name]

 *Our expeditionary forces have liberated [colony name] from the mutated horrors that were occupying our main settlements. Their rotting corpses are now littering the ground, and our troops are currently in the process of bulldozing the putrid bio-mass into hastily dug landfills.

Pockets of survivors are emerging all across the [planet or moon], but many lives have been lost.*