Core
The scorching, molten heart of the planet where danger meets infinite energy.
The Core represents the deepest, most volatile layer of the planetoid in Oxygen Not Included, serving as the ultimate frontier for ambitious duplicants. Located at the very bottom of the asteroid, this region is defined by extreme heat, high pressure, and a unique geological composition that defies standard mining logic. It acts as both the planet's engine and its graveyard, where resources are abundant but survival requires advanced technology and careful thermal management.
- Location
- Deepest planetary layer (bottom of the asteroid)
- Primary Composition
- Obsidian, Igneous Rock, and pockets of Magma
- Key Resource
- Magma
- Pressure Level
- Critical/High
- Accessibility
- Requires Advanced Drilling or Deep Tunneling
Lore & Background
For the colony, the Core is a paradox of opportunity and peril. It holds the most potent heat source available: Magma. This molten rock can be used to heat water into steam, which then drives turbines to generate massive amounts of power, or to smelt materials at incredible speeds. However, accessing it requires duplicants to brave environments where standard tools melt and oxygen becomes scarce due to heat expansion. The lore suggests that the Core is not just a resource depot but the living pulse of the planetoid, a place where the boundary between solid matter and liquid energy blurs.
In Their Own Story
The drill bit spun wildly, vibrating against the rock face as the temperature gauge on the wall screamed in red. Below, through the reinforced glass viewport, a river of glowing orange lava churned violently, illuminating the dark cavern with an eerie, pulsating light. 'It's hotter than the simulation predicted,' the lead engineer muttered, adjusting her thermal suit's cooling unit, which was already whining under the strain. The air shimmered with heat haze, distorting the view of the magma ocean that stretched endlessly into the gloom. One wrong move, one cracked pipe, and this pocket would become a tomb. But as the pump engaged and the first stream of molten rock surged upward, the colony's power grid flared to life, promising warmth for everyone above.
Reader's Guide
The primary hazard is Magma, a liquid resource that deals massive damage and creates instant steam upon contact with water or low-temperature gases. Resource distribution is dominated by Superheated Magma flows and pockets of high-pressure gases like Steam and Carbon Dioxide. Solid rocks here are rare but may include valuable minerals if cooled rapidly. The environment is naturally pressurized, requiring careful venting to prevent explosive decompression events. Extraction requires specialized equipment such as Thermal Insulators to protect tunnels and Magma Pumps to safely transport the liquid. Players must avoid mixing water with magma to prevent steam explosions. Constructing a dedicated thermal sink or using heat exchangers is essential to manage the ambient temperature before establishing a permanent mining outpost.
Did You Know?
- Magma in the Core can be used to heat water into steam, which then powers turbines to generate electricity.
- The extreme heat of the Core causes gases to expand rapidly, often creating high-pressure pockets that require careful venting.
- Duplicants cannot survive in the Core without active cooling systems due to the ambient temperature.
- Drilling into the Core is one of the most dangerous activities a colony can undertake due to the risk of magma leaks and explosions.
Gallery






Frequently Asked Questions
Where is the Core biome located on the planetoid?
It sits as the deepest planetary layer, positioned directly beneath both the Crust and Mantle regions. This location makes it the ultimate frontier for duplicants willing to brave the extreme conditions found at the bottom of the world.
What is the primary resource found in the Core layer?
Superheated Magma is the key resource available here, serving as a powerful energy source for base operations. Extracting it requires careful planning because of its volatile nature and the surrounding geological composition.
How can duplicants reach the Core from the surface?
Access requires advanced drilling tools or deep tunneling strategies to penetrate the upper planetary layers. It is not accessible through standard early-game mining methods due to the depth and pressure involved.
Why is the Core considered a high-risk area for colonies?
This region acts as both an engine and a graveyard, featuring critical pressure levels that threaten unprepared explorers. Survival depends on maintaining strict thermal management while navigating this unstable geological zone.
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