The Matriarch's Departure

Lore & Background

In the world of Oxygen Not Included, the duplicants are a small cadre of colonists dispatched aboard a colony ship to seed a new world. The Matriarch, the ship's governing intelligence, orchestrates every phase of the voyage—from cryogenic transit through atmospheric entry to the initial surface touchdown. She is the voice in the overhead speakers, the hand that allocates rations and schedules shifts. For the duplicants, she is as much a parent as a pilot.

When the Matriarch's departure sequence initiates, the colony ship completes its delivery and pulls away from the planet. The overhead lights dim to a standby hum. The automated provisioning systems that had been quietly keeping the duplicants fed and hydrated wind down. What remains is a pocket of carved-out rock, a handful of basic machines, and a group of small, wide-eyed colonists who must now keep their own air breathable, their own water drinkable, and their own bodies warm. The Matriarch's final transmission is not a command but a parting: she has done her part, and the rest belongs to them.

For the player, this mission is the emotional and mechanical threshold. The cozy tutorial scaffolding is stripped away. Oxygen is no longer a background assumption; it is a resource that must be generated, routed, and monitored. The duplicants' needs—hunger, thirst, temperature, sanity—shift from occasional prompts to a constant, interlocking web. The Matriarch's absence is felt most in the silence where her scheduling voice used to be. The colony must now run itself, and the player must learn to think in systems rather than in tasks.

In Their Own Story

The last thing Mara heard before the hum faded was the Matriarch's voice, soft and almost apologetic, like a mother tucking in a child who will have to make her own breakfast tomorrow. 'You are ready,' it said, and then the overhead panels went dark one by one, a slow blink of amber to black, and the colony ship's shadow slid away from the planet's surface like a hand withdrawing from a shoulder.

Mara set down her half-eaten ration. Beside her, a younger duplicant stared up at the ceiling as though expecting the lights to come back. They didn't. The air recyclers kept turning—clunk, whoosh, clunk, whoosh—but the rhythm felt different now. Smaller. Like a heartbeat that belonged only to them.

'Right,' Mara said, and picked up her wrench. The rock was cold. The pipes were waiting. And for the first time, nobody was telling them what to do next.

Reader's Guide

Objective: Survive and establish a self-sustaining colony after the Matriarch's departure. The player must ensure all duplicants' needs—oxygen, water, food, and temperature—are met indefinitely.

Starting conditions: A small group of duplicants in a pre-carved pocket of rock. Basic infrastructure is in place (a few air recyclers, a water source, basic power), but it is minimal and not yet sufficient for long-term survival. The colony ship is gone; no external resupply will arrive.

Key triggered events: Early in the mission, the Matriarch's departure sequence plays, and automated support systems (provisioning, scheduling) shut down. Duplicants begin expressing needs more frequently. As the colony grows, new duplicants may arrive or be awakened, increasing demand on every resource.

Win condition: Maintain all duplicants' survival needs (oxygen above critical threshold, water available, food available, temperature within survivable range) for the duration of the mission without any duplicant dying from neglect. The mission completes when the colony reaches a stable, self-sustaining state.

Lose condition: One or more duplicants die due to oxygen depletion, dehydration, starvation, or extreme temperature. The colony is considered lost.

Player response options: Prioritize which duplicants to keep alive if resources are scarce. Decide whether to expand the colony upward or deeper. Choose which machines to build first (oxygen generators, water purifiers, food production). Manage power generation and distribution. Assign duplicants to tasks based on their traits and preferences.

Did You Know?

• The Matriarch's departure is the narrative hinge that transforms Oxygen Not Included from a guided setup into a genuine survival challenge—the player's first true 'no safety net' moment.
• In ONI's cross-section view, the colony ship's departure is represented visually by the upper rock layers and surface elements fading or shifting, reinforcing that the duplicants are now sealed underground.
• The mission's design philosophy mirrors real colony-ship scenarios: once the launch vehicle is gone, the settlers must generate every calorie, every liter of water, and every breath of air from local resources.
• Duplicants in ONI have individual traits and preferences that affect morale and task efficiency, making the post-departure management of a small group feel surprisingly personal despite the industrial setting.