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Oxygen Not Included Wiki

Mods Guide: Best Mods & How to Install

Mods extend Oxygen Not Included by adding content, changing UI, and exposing game data for user-created assets and behaviors. Modding enables new tools, buildings, overlays, elements, animations, and gameplay scenarios—but it requires care: the game can be unstable when modded, and some base systems were specifically refactored to make modding safer and easier.

Getting started

  • Subscribe and enable: Use the Steam Workshop to subscribe to mods. In-game, open the Mods menu, check the mods you want, and restart the game to load them.
  • Debug & Sandbox tools: Use Debug mode (Backspace toggle on PC) to speed testing: reveal the fog of war, copy/paste map regions (including buildings and their contents), paint elements, and spawn Duplicants. Sandbox modes and debug spawn commands make validating mods and scenarios faster.

What the game exposes to modders

Recent engine and data changes were made specifically to make modding feasible and more robust:

  • Plan/Build menus and Tools: Build categories and the Tools menu are now implemented as dynamic collections (lists/hashes) so mods can add new tools and menu entries without conflicting with game enums.
  • Overlays: Overlays were converted to hash-backed tables so mods can add overlays or hook into overlay initialization.
  • Elements and Substances: The Substances data structure was cleaned and unused fields removed; the Filter screen shows mod-added elements.
  • Animations & assets: Startup order was adjusted so mod-added animations and assets can register. ModUtil was added to ensure required anims and assets are loaded.
  • Materials and elements: Base material stubs for solids and liquids exist to simplify creating mock materials for prototypes.
  • Database and logging: Error reporting for bad keys improved, and more mod-loading errors are sent to logs; startup errors have a better chance of showing a crash screen.

These changes let modders add new buildings, materials, elements, UI entries, and other content more reliably.

Typical mod content

  • New buildings and stations: Mods commonly add buildings to the build menu, including new functional stations (research/production) and decorative structures. Because the plan screen is now extendable, a mod can add whole categories.
  • New elements and substances: Mods add gases, liquids, and solids. The Filter and Substance systems accept mod-added elements so they appear in UI filters and overlays.
  • New overlays and tools: Mods can register custom overlays (for example, a visual indicator for a new resource or hazard) and tools for placement and editing.
  • Animations and skins: Modders supply anim files and skins. Use ModUtil and place anims in the proper asset folders so the game loads them on startup.
  • Scenario / Lab-style content: Mods can create alternate asteroid layouts and scenario content that behaves like The Lab, enabling challenge asteroids, custom missions, or event-style gameplay.
  • Cosmetic items and rewards: Special skins and cosmetic unlocks can be distributed through mods or tied to external reward systems.

Development workflow & tips

  • Start small: Add one building or element and verify it appears in the build menu and overlays before expanding.
  • Use the provided utilities: ModUtil and the new list/hash-backed systems reduce common errors. Ensure any anims or assets referenced are included and registered.
  • Check logs: The improved database and mod-loading logs will point to bad keys and missing references. Fix errors reported during startup.
  • Test with Debug mode: Use Backspace debug features to paint elements, spawn items, and copy/paste templates for rapid iteration.
  • Be mindful of stability: The game’s modding support was improved but modding can still introduce crashes or save incompatibilities—test saves across sessions and watch for startup errors.

Advanced possibilities and caveats

  • Replace or extend UI categories safely: Because categories are hashes, you can add new entries; avoid reusing existing keys to prevent collisions.
  • Elements & gameplay balance: Adding a new gas or liquid is supported, but ensure you set appropriate physical properties; the game enforces one element per cell and various thermal/phase behaviors that interact with base systems.
  • Rocket/space interactions and exploits: The game world contains special contexts (for example, rocket modules and station interiors). Modded content that interacts with special bounds or insulated areas can unintentionally enable exploits (expanded usable space, indestructible walls, etc.). Test interactions in edge cases such as rocket interiors, stations, and vacuum.
  • Asset sizes & visuals: DLC and base game sometimes use different sprites or sizes for similar buildings (for example Cargo Bay visuals differ by Spaced Out content). When creating assets, include correct sizes and variants if you intend compatibility with DLC content.

Distribution and user experience

  • Provide clear install instructions: Tell users how to subscribe, enable the mod, and whether it requires other mods or DLC.
  • Compatibility notes: State which game versions and DLC your mod supports, and whether saves made with the mod are compatible with the base game without it.
  • Offer presets and examples: Ship a sample asteroid or template, and include recommended settings for any custom overlays or tools.

Resources useful to modders

  • ModUtil and the new list/hash-backed collections are the primary helpers for registering assets and UI entries.
  • Use debug tools for rapid testing: paint elements, copy/paste templates, and spawn Duplicants and items.
  • Read mod-loading logs at startup to catch missing keys, missing anims, or database problems.

Modding in Oxygen Not Included is now far more practical thanks to structural changes to menus, overlays, substances, and asset loading. With careful testing and attention to stability, mods can add compelling new gameplay, visuals, and scenarios to the game.

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