Oxygen Not Included: March 2026 Bug Fix Update

Hi everyone,

Our March 2026 Bug Fix Update goes live today!

For this free update, we focused on squashing a bunch of bugs. We also made some changes to the sim and upgraded the version of the Unity engine we use. Everything mentioned in this post applies to all versions of ONI.

Highlights

• Upgraded Unity

• Modified the temperature exchange formula to be less error-prone.

• Small masses (micrograms) now exchange temperature in the sim.

• Fixed a number of bugs with off-gassing liquids.

• Domesticated plants no longer consume fertilizer while wilted.

• Hidden fog of war tiles associated with POIs will now be correctly revealed. This will not fix existing saves.

• Fixed open doors transferring temperature in a vacuum.

• Batteries no longer function when entombed.

A little more detail...

We tweaked the formula we use for temperature exchange for tiles and debris, making it more stable for small fluctuations and oscillations. It should feel the same, just less buggy! We've also added temperature exchange for small masses, which should clear up the issues folks were experiencing when using the Conveyor Rail Element Sensor to separate out cooled elements from hot ones.

Off-gassing liquids that were emitting gases in the wrong amount or at the wrong temperature, removing more liquid than intended, and/or deleting mass from the tile below them... will no longer do that! Whew.

Ugly Criers now produce the expected volume of tears. Previously, some tears were evaporating instantly because they didn't have enough mass. Now, Dupes will hold back their tears until they've got enough mass built up to properly open the floodgates of emotion. Meanwhile, Duplicants who share the same name will no longer mistakenly share the logging of their stress modifiers in UI screens.

Open doors will no longer cause temperature to be exchanged in a vacuum. This resolves issues where open mechanized airlocks could erroneously transfer heat, and should also resolve instances of gases not flowing through open doors.

In new games, POIs that are hidden behind fog of war will now be revealed correctly.

Summary

We took a break from paid DLCs to fix bugs! Hopefully, this helps everyone's colonies chug along more smoothly - surviving in space is challenging enough already.

Found new bugs? Report 'em here. Got feedback? Let us know here! Your insights are super valuable to us. Thank you so much for playing!

Full patch notes

Changes and Improvements

• All versions

  • Upgraded to Unity 6.3.

  • Made adjustments to the Printing Pod sidescreen UI Layout and added a Research button.

Fixes

• All versions

  • Simulation

    • Removed lower mass limit for temperature exchange in the sim for tiles and debris.

    • Tweaked the formula we use for temperature exchange for tiles and debris, making it more stable for small fluctuations and oscillations

    • Fixed a bug where material that didn't exchange temperature would not consider changing state.

    • Fixed bugs where off-gassing liquids in the sim could emit the wrong amount of gas, emit it at the wrong temperature, remove more liquid than was intended, and/or delete mass from the tile below them.

  • Batteries no longer function when entombed.

  • Percentages displayed in the UI no longer round up to 100%, to avoid confusion in cases where the real number is actually slightly lower (e.g. 99.6%).

  • Domesticated plants no longer consume fertilizer while wilted.

  • Nosh Beans, Sleet Wheat Grain, and Mimillet will now rot while marked for compost, and retain their rot value if the compost request is cancelled.

  • Adjusted mouse drag threshold before a click is interpreted as a drag, to reduce mislicks on