Oxygen Not Included stands out as a challenging space-colony simulation game available on PC, where players manage a group of colonists, known as Duplicants, stranded on an asteroid. Developed by Klei Entertainment and released in 2019, this indie title combines survival elements with deep simulation mechanics, forcing you to handle resources like oxygen, food, and power while expanding your base underground. The core appeal lies in balancing environmental factors and colonist needs to turn a fragile outpost into a sustainable habitat.
Gameplay
In Oxygen Not Included, the gameplay revolves around excavating and constructing a functional base within a procedurally generated asteroid. You start with a few Duplicants who dig for resources, build structures, and set up systems for essentials like plumbing and electricity. Resource depletion begins immediately, so efficient allocation is key to survival. The game simulates complex physics, including gas flow for oxygen and carbon dioxide management, liquid piping for water and waste, and thermal regulation to prevent freezing or overheating.
Stress plays a significant role, as Duplicants can react poorly to harsh conditions, leading to behaviors that disrupt operations. To counter this, you provide leisure options, better living quarters, and quality food. Power generation comes from sources such as coal generators or hydrogen setups, requiring careful grid management to avoid overloads. Recycling is emphasized, turning waste into fuel or air, and even harnessing creature byproducts for sustainability. Exploration involves generating new worlds, each with unique biomes and challenges.
Game Modes
Oxygen Not Included focuses on a single-player survival simulation mode, where you guide your colony from basic survival to advanced thriving. The base game offers procedural world generation, allowing you to create new asteroids with varied layouts and resources at the start of each playthrough. There are no multiplayer options or distinct competitive modes; instead, the emphasis is on solo management and experimentation.
Expansions like the Spaced Out! DLC introduce multi-asteroid colonies, enabling rocket travel between worlds and adding layers to resource gathering and base expansion. Other DLCs, such as The Frosty Planet Pack, bring new biomes with cold environments and specialized tools, while The Prehistoric Planet Pack adds ancient creatures and tech. These expansions enhance the core mode without creating separate game types, offering fresh starts with modified rules and content.
Core Mechanics
Key mechanics in Oxygen Not Included include detailed simulations of gases, liquids, and heat. For instance, the oxygen overlay lets you visualize air movement in real time, helping monitor generation and pollution. Power systems demand balancing production and consumption, with options like natural gas or manual labor. Duplicant traits affect their efficiency, and you must assign tasks based on skills to optimize productivity.
Wildlife interaction adds depth, as creatures can be farmed for food or materials, and their natural processes contribute to recycling loops. The game's thermodynamics require insulating areas or using devices to control temperatures, preventing crop failure or equipment damage. These interconnected systems create a puzzle-like experience, where one oversight can cascade into colony-wide issues.
Is It Worth Playing?
For those who enjoy intricate simulation games with high replayability, Oxygen Not Included remains a strong choice in 2026. It holds an Overwhelmingly Positive rating on Steam, with 96% of 130,275 reviews being positive, reflecting strong community approval. The active player base, ranking it as the 462nd most played game in February 2026 according to Newzoo, shows ongoing interest.
Recent DLC releases like The Frosty Planet Pack and The Prehistoric Planet Pack keep the content fresh, expanding mechanics without requiring constant developer updates. If you prefer strategic depth over fast action, and don't mind a steep learning curve, this game delivers lasting value through its procedural challenges and mod support from the community. It's particularly suited for players interested in engineering and problem-solving in a sci-fi setting.
