''Oxygen Not Included'' is a 2019
survival
Survival or survivorship, the act of surviving, is the propensity of something to continue existing, particularly when this is done despite conditions that might kill or destroy it. The concept can be applied to humans and other living things ...
simulation video game
Simulation video games are a diverse super-category of video games, generally designed to closely simulate real world activities. A simulation game attempts to copy various activities from real life in the form of a game for various purposes such ...
developed and published by
Klei Entertainment
Klei Entertainment Inc. ( ) is a Canadian video game development company located in Vancouver, British Columbia. Klei was formed in July 2005 by Jamie Cheng. Their best-known titles include '' Don't Starve'' and '' Oxygen Not Included''.
On Jan ...
. After being released on
Steam
Steam is water vapor, often mixed with air or an aerosol of liquid water droplets. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Saturated or superheated steam is inv ...
's
early access
Early access, also known as alpha access, alpha founding, paid alpha, or game preview, is a funding model in the video game industry by which consumers can purchase and play a game in the various pre-release Software release life cycle, developm ...
since February 2017, the game was officially released on July 30, 2019.
Gameplay
''Oxygen Not Included'' is a
simulation
A simulation is an imitative representation of a process or system that could exist in the real world. In this broad sense, simulation can often be used interchangeably with model. Sometimes a clear distinction between the two terms is made, in ...
survival game
Survival games are a subgenre of action games which are often set in hostile, intense, open-world environments. Players generally start with minimal equipment and are required to survive as long as possible by finding the resources necessary t ...
.
At the start of a new game, three colonists (referred to as duplicants) find themselves in an asteroid with isolated pockets of breathable atmosphere, with no memory of how they got there. The player is tasked with managing and taking care of these duplicants as they try to survive and create a sustainable makeshift
space colony. The player must monitor the duplicants' hunger, waste, and oxygen levels to keep them alive.
Each game's world is
procedurally generated
In computing, procedural generation is a method of creating data algorithmically as opposed to manually, typically through a combination of human-generated content and algorithms coupled with computer-generated randomness and processing power. I ...
.
The world is then subdivided into various regions or "biomes" that contain different and often biome specific materials and critters. While initial areas have a breathable atmosphere, subsequent areas are in a
vacuum
A vacuum (: vacuums or vacua) is space devoid of matter. The word is derived from the Latin adjective (neuter ) meaning "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressur ...
or lack oxygen, requiring proper preparation by the duplicants before they explore these areas. The world also contains several hazards such as diseases and extreme temperatures. The game simulates the
diffusion
Diffusion is the net movement of anything (for example, atoms, ions, molecules, energy) generally from a region of higher concentration to a region of lower concentration. Diffusion is driven by a gradient in Gibbs free energy or chemical p ...
of gases and equalization of atmospheres when a new natural chamber is opened, which can cause oxygen levels to drop in existing chambers, as well as the draining of liquids by gravity.
To help establish the colony, the player directs the duplicants to perform certain tasks, such as mining for resources, growing food, crafting equipment, researching new technologies, and maintaining their own health through nourishment, rest, and hygiene.
The player does not control the duplicants directly, and instead provides prioritized instructions, from which the duplicants will then follow to the best of their abilities. For example, the player can order a conduit of wire to be built; which will have the duplicants collect the materials to make the wire, clear away any materials around the conduit's path, and then construct the wire. If the duplicants cannot access a source of copper for the wire, the task will remain uncompleted as the duplicants go to complete other tasks they can do. Duplicants have stats that determine how effective they are at certain tasks, and will prioritize tasks that they are best at. These duplicants' skills can be improved over time and practice.
Development and release
''Oxygen Not Included'' is developed by
Vancouver
Vancouver is a major city in Western Canada, located in the Lower Mainland region of British Columbia. As the List of cities in British Columbia, most populous city in the province, the 2021 Canadian census recorded 662,248 people in the cit ...
-based indie studio
Klei Entertainment
Klei Entertainment Inc. ( ) is a Canadian video game development company located in Vancouver, British Columbia. Klei was formed in July 2005 by Jamie Cheng. Their best-known titles include '' Don't Starve'' and '' Oxygen Not Included''.
On Jan ...
.
The game was announced for
Windows
Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...
during the PC Gaming Show at the
Electronic Entertainment Expo 2016
The Electronic Entertainment Expo 2016 (E3 2016) was the 22nd E3, during which hardware manufacturers and software developers and publishers from the video game industry presented new and upcoming products to attendees, primarily retailers and ...
.
It was also revealed that the game would come to
macOS
macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...
and
Linux
Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...
. An in-development version of the game was made available via
early access
Early access, also known as alpha access, alpha founding, paid alpha, or game preview, is a funding model in the video game industry by which consumers can purchase and play a game in the various pre-release Software release life cycle, developm ...
on February 15, 2017.
The game was originally stated to leave early access on May 28, 2019,
but was pushed back to July 2019. Klei also announced plans to make
downloadable content
content (DLC) is additional content created for an already released video game, distributed through the Internet by the game's publisher. It can be added for no extra cost or as a form of video game monetization, enabling the publisher to gain ad ...
for the game.
DLC has since been added, such as the free Automation Innovation update (extending the current automation system, adding equipment such as
ribbon cable
A ribbon cable is a cable with many conducting wires running parallel to each other on the same flat plane. As a result, the cable is wide and flat. Its name comes from its resemblance to a piece of ribbon.
Ribbon cables are usually seen fo ...
s) and the paid Spaced Out update (adding a
radiation
In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or a material medium. This includes:
* ''electromagnetic radiation'' consisting of photons, such as radio waves, microwaves, infr ...
system,
uranium refinement, and
bee ranching). Klei has stated that there will be no more DLCs for ''Oxygen Not Included'' going forward, opting for free updates instead. That being said, the game then released two extra DLC packs years later: ''The Frosty Planet Pack'' on July 19, 2024, and ''The Bionic Booster Pack'' on December 13, 2024.
Klei's Johann Seidenz said that games such as ''
Dwarf Fortress
''Dwarf Fortress'' (previously titled ''Slaves to Armok: God of Blood Chapter II: Dwarf Fortress'') is a construction and management simulation and roguelike indie video game created by Bay 12 Games. Available as freeware and in development si ...
'', ''
Prison Architect
''Prison Architect'' is a private prison construction and management simulation video game developed and published by Introversion Software. It was made available as a crowdfunded paid alpha pre-order on September 25, 2012 with updates that were ...
'', and ''
The Sims
''The Sims'' is a series of life simulation video games developed by Maxis and Video game publisher, published by Electronic Arts. The franchise has sold nearly 200 million copies worldwide, and is one of the List of best-selling video game fran ...
'' influenced the design of ''Oxygen Not Included''.
Lore of the game
Through playing the game, by 'inspecting' certain pre-existing structures laid out randomly throughout the map, players can discover and put together story elements (also referred to as 'log entries') of the ''Oxygen Not Included'' universe:
Setting
The events of ''Oxygen Not Included'' take place in the distant future (potentially during the 23rd century).
The Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all of Earth's water is ...
has suffered catastrophic
environmental degradation
Environment most often refers to:
__NOTOC__
* Natural environment, referring respectively to all living and non-living things occurring naturally and the physical and biological factors along with their chemical interactions that affect an organism ...
. Fossil fuels have been depleted, nuclear energy is highly restricted, and the atmosphere is choked with pollution. Conventional solar power is insufficient, and global conflicts over resources have intensified.
Gravitas
In response to the escalating ecological crisis, Dr. Jacquelyn Stern founded Gravitas, a scientific research organization dedicated to solving the energy crisis. Gravitas quickly became a powerful institution, producing technologies such as molecular forges and thermal nullifiers. However, its core objective was much more ambitious: enabling time travel and interstellar colonization.
The centerpiece of this effort was the Human Colonization Initiative, a project aimed at establishing human life on distant, potentially habitable asteroids. To address the logistical challenges of transporting materials and personnel via spacecraft, Gravitas developed Printing Pods—devices capable of 3D-printing infrastructure, resources, and even sentient workers directly on arrival.
Genetic Engineering and Duplicants
To further support extraterrestrial colonization, Dr. Olivia Broussard, a geneticist and former colleague of Dr. Stern, was enlisted to engineer lifeforms suited for survival on alien planets. These organisms—including plants, animals, and microbial life—are found throughout the game and are assumed to be biotechnological constructs developed at and by Gravitas.
The workforce for these colonies consists of Duplicants, artificial human-like beings created through biological printing technology. Initial experiments involved non-human
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
, but human genetic material—often sourced without consent—was soon incorporated. Many Duplicants are clones or imitations of actual Gravitas employees. Due to security concerns, biometric locks were installed in the Gravitas facility to prevent the originals from accessing certain areas.
Gravitas' collapse and abandonment
At some point, Gravitas experienced an internal disaster. Clues scattered throughout in-game ruins, such as corrupted logs and malfunctioning equipment, suggest a containment failure, possibly linked to overuse of teleportation or cloning technologies. The facility was abandoned, and the project was never completed.
The player's colony is one of the surviving automated outposts, activated long after Gravitas's fall. The Duplicants operate without direct oversight, guided only by the systems left behind.
Asteroid Colonies
Each game begins with Duplicants arriving on a randomly generated asteroid, referred to in-game as a “planetoid.” These asteroids are artificial environments seeded with Gravitas-engineered ecosystems, machinery, and infrastructure. Although they appear naturally formed, many elements—such as perfectly rectangular ruins, mechanical POIs (points of interest), and printed resources—imply that they were prepared or altered by Gravitas prior to the catastrophe.
These planetoids often contain remnants of Gravitas installations, including research stations, laboratories, and transit tubes. The presence of automated message terminals and storage lockers containing personal effects indicates that Gravitas employees once lived and worked on-site. Some asteroids also feature temporal tear anomalies, suggesting experimental teleportation or time-manipulation technologies may have destabilized local reality.
The Temporal Tear and the Universe's Fracturing
One of the core mysteries of the game is the Temporal Tear—a cosmic rift discovered in the late stages of gameplay. In the ''Spaced Out!'' DLC, players can construct rockets and travel to other asteroids, eventually building a Temporal Tear Opener. Once activated, this device allows access to a realm beyond conventional space-time.
Lore fragments suggest that Gravitas’ experiments with teleportation and time travel may have damaged the fabric of the universe. The Temporal Tear appears to be both a symptom and a byproduct of these experiments. Some speculate that the Duplicants’ continuous existence in isolated pocket-dimensions may be the result of a fragmented reality, where time loops, causality breaks down, and remnants of Gravitas’ projects continue functioning in isolation.
Post-Gravitas Autonomous Operation
The game world implies that Gravitas’s infrastructure, including Printing Pods and research computers, continue to operate autonomously. Duplicants are printed without external commands, suggesting a failsafe or self-preservation directive. As there are no signs of external communication or central oversight, each colony is effectively a self-contained experiment or survival scenario.
This autonomy is reinforced by the absence of any surviving human authority. Although Duplicants bear the names and appearances of Gravitas employees, they have no memories of their predecessors and operate more like programmed entities than true individuals. Whether this was Gravitas’s intended outcome or a consequence of the organization's downfall is left unresolved.
Reception
Reviews
Review aggregator
A review aggregator is a system that collects reviews and ratings of products and services, such as films, books, video games, music, software, hardware, or cars. This system then stores the reviews to be used for supporting a website where user ...
Metacritic
Metacritic is an American website that aggregates reviews of films, television shows, music albums, video games, and formerly books. For each product, the scores from each review are averaged (a weighted average). Metacritic was created ...
gave the game a score of 86/100, meaning "Generally Favorable".
Nate Crowley, writing for
Rock Paper Shotgun
''Rock Paper Shotgun'' is a British video game journalism website. It was launched in July 2007 to focus on PC game, PC games and was acquired by Gamer Network, a network of sites led by ''Eurogamer'', in May 2017.
History
''Rock Paper S ...
praised the game's design and progression, but questioned the ever-growing complexity as a deterrent to more casual gamers, especially those without backgrounds in science and engineering.
GameCentral
''Metro'' is a British freesheet tabloid newspaper published by DMG Media. The newspaper is distributed from Monday to Friday mornings on public places in areas of England, Wales and Scotland (excluding public holidays and the period betwee ...
also gave the game positive reviews, with a total 8/10, praising the scientific accuracy as well as the design, but raising concerns about the difficulty, especially with the lack of in-game learning tools.
Accolades
''Oxygen Not Included'' was nominated for "
Strategy/Simulation Game of the Year" at the
23rd Annual D.I.C.E. Awards, and for "Strategy/Simulation" at the 2020
Webby Award
The Webby Awards (colloquially referred to as the Webbys) are awards for excellence on the Internet presented annually by the International Academy of Digital Arts and Sciences, a judging body composed of over three thousand industry experts a ...
s.
References
External links
*
{{Klei Entertainment
2019 video games
Early access video games
Klei Entertainment games
Simulation video games
Survival video games
Video games developed in Canada
Windows games
Linux games
MacOS games
Indie games
Single-player video games