[Game Update] - 719533

[JarrettM]

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 below.
 

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 buttons.
  • Hidden fog of war tiles associated with POIs will now be correctly revealed. This will not fix errant tiles in existing saves.
  • Duplicants with the same name will no longer share logging of stress modifiers in UI screens.
  • Ugly Criers will now weep the correct volume of tears.
  • Doors
    • Fixed doors exchanging temperature while open in a vacuum due to automation signals causing them to be in an incorrect state.
    • Door access control change requests will now persist in save files.
    • Fixed an issue where applying copy settings to both tiles of a door resulted in the settings being applied twice, undoing the settings change. This may fix other copy settings bugs as well.
  • Power System
    • Computing the maximum safe wattage of a building on an electrical network (Properties tab > Circuit Overview), now considers joint plates that are part of that circuit, as well as wires. Prior to this change, joint plates were not considered.
    • Disabled power transformer buildings will no longer incorrectly display the No Wire status.
    • An electrical circuit with a broken Wire Bridge will no longer initialize as connected when loaded from a save game.
    • Fixed an issue where a Power Shutoff constructed on an inactive logic network would default to active. The default behaviors are now:
      • No logic network: active.
      • Inactive (red signal) logic network: deactivated.
      • Active (green signal) logic network: active.
  • Critters
    • Fixed Pacus playing idle animation when a wrangle errand is created or cancelled.
    • Fixed Bammoth and Hatch missing ropes when wrangled.
    • The "No Critters Available" status for Shearing Station, Grooming Station and Milking Station is now "No Critters Ready." This avoids confusion in situations where there are shearable critters nearby who are not yet ready to have their shearables harvested.
    • The Critter Fountain's contents no longer exchange temperature with the environment.
    • The Milking Station description has been updated to include Husky Moos and biodiesel.
  • Pitcher Pump
    • Fixed a bug where Pitcher Pumps would report incorrect volumes of available liquids.
    • Fixed Duplicants occasionally becoming infinitely stuck using a Pitcher Pump at single tile depth.
    • The Pitcher Pump will no longer extract liquids from outside the visually indicated area of interaction.
  • Story Traits
    • Fixed a bug where Fossil Fragments marked for excavation were not creating an errand on load.
    • Fixed Somnium Synthesizer not consuming small amounts of Dream Journals correctly, which was preventing it from accepting delivery requests for more Dream Journals.
    • The Wall Chart prop in the Printerceptor POI now unlocks only the next journal entry. It previously had a specific entry to unlock first.
  • Fixed a bug where irrigated plants using the Hydroponic Farm were growing and unbothered by the lack of irrigation when loading a save where those plants had been wilted due to insufficient amounts of liquid in the farm tile.
  • Fixed a bug that was causing Command Capsules and Spacefarer Modules to fail to show player-customized names in the Details screen title bar.
  • Previews for striped and curved drywall blueprints under construction will better match the completed building.
  • Splash effect now plays correctly when things fall into liquid.
  • Fixed bug preventing certain plant seeds from being displayed on Pedestals, Shelves, and Sweepies.
  • Fixed an issue where timers on Filter/Buffer Gates were inaccurate.
  • Fixed items no longer exchanging temperature with their environment after being removed from a Refrigerator.
  • The Liquid Shutoff will now retain the current flow it was saved with, rather than resetting to 0 on load.
  • Duplicants with the Banshee stress reaction will now wail if the reaction triggers while they are standing in liquid.
  • Fixed building lights appearing invisible when loading saves.
  • Minor adjustments to Research sidescreen layout on research stations.
  • The Apothecary's Effects panel now mentions that it produces medical supplies.
  • Fixed "Plant" sidescreen button and Emulsifier building translations in Korean localization.
  • Right-clicking will no longer also register as a left-click on UI widgets.
  • Fixed an issue where names of items in storage were truncated too early. Adjusted the font.
  • Corrected an error in the values displayed by the Condition Panel's Body Temperature tooltip.
• Base game only
  • Fixed a crash that would occur when selecting a space destination with a modded element no longer present in the game.
  • The Telescope building's description no longer mistakenly states that it produces Data Banks.
  • Added Data Bank production information to the Enclosed Telescope's database entry.
• Spaced Out! only
  • Fixed an issue where deconstructing a Solo Spacefarer Nosecone and building a Spacefarer Module resulted in some tiles not being buildable.
  • Fixed an issue where the Orbital Cargo Module was not requesting materials upon landing.
  • The Telescope and Enclosed Telescope buildings' descriptions now both specify that they produce Data Banks when revealing starmap hexes. They also list Data Bank production in their Effects panels.
  • Fixed the "Thrilling Flight" status item persisting on Duplicants even when they were no longer in space.
  • Fixed Hatches not having shadows in the Critter Cargo Bay.
  • Selecting a roundtrip rocket while it's mining a Space POI will now show the name of the pending roundtrip destination in their UI.
  • Corrected a typo in the database entry for Plug Slugs.
• The Bionic Booster Pack
  • Fixed an issue where Bionic Duplicants would not consider power banks, oxygen canisters, or Gear Balm inside rockets if they were on the main asteroid.
  • Fixed Flydo attempting to pick up things through doors and then failing because they can't reach the specific cell.
  • Fixed a crash that could happen when Flydo evaluated errands.

Modding

• Upgraded Unity version to 6000.3.5f2.
• Upgraded Harmony to 2.4.2.
• Fixed the infinite loop of "restart to re-install mod" in the presence of disk I/O errors.
• Handle file I/O errors that may occur when installing a mod from its source.
• When a mod is pending a re-install, it will display its version as "Re-install Pending" to avoid confusion over what version is installed or loaded.
• Given the changes to Unity in version 6, we feel the best starting point for mod development is .NET Standard 2.1. We believe this because some uses of .NET Framework are not cross-platform compatible, and we expect future changes will make increased use of types that require .NET Standard 2.1, such as Span. We will, however, continue to build ONI using Unity’s .NET Framework API Compatibility Target.
• Added a Mod Safe Mode. If the game crashes before the main menu it will load into Mod Safe Mode next time the game starts. In safe mode, mods are not loaded. This offers an opportunity to disable mods before restarting.
  • Mod Safe Mode is disabled if a dev mod is enabled.
  • Mod Safe Mode can be disabled by editing your kplayerprefs.yaml using the int key DisableAutoModSafeMode. For advanced users only.
• As part of the Unity upgrade, TextMeshPro was updated. If your mod interacts with TextMeshPro, or you use a modding library that does, there might be some breaking changes to review.
  • Modified TextMeshPro to include the unused variable TMP_Text.ignoreRectMaskCulling. This prevents an issue with mods using PLib after the Unity upgrade.
  • Added TMP_InputField.DeactivateInputField() with no parameters as this was a common failure of a number of mods.
• Added a helper function Texture2D ModUtil.LoadTexture(string) to allow .NET Framework targeting mods an alternative to Texture2D.LoadImage(byte[]) which has a Span overload causing compilation issues.

View full update

[sakura_sk]

Button was not pushed...

[gigamoi]

Looking for April fool's day prank... (It was posted on 01/04/2026 where I live so I'm expecting a europe+africa+asia+australia only prank.)

Edited April 1 by gigamoi

[GluttonyMain]

Sounds awesome

[sakura_sk]

On 4/1/2026 at 1:46 AM, JarrettM said:

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.

Did that sim change also change how doors closing on top of gases/liquids behave? A door closing previously displaced gases or liquids consistently. That doesn't seem to be the case anymore

[sakura_sk]

On 4/1/2026 at 1:46 AM, JarrettM said:

Fixed doors exchanging temperature while open in a vacuum due to automation signals causing them to be in an incorrect state.

Or perhaps that fix broke mechanized airlock consistency?

[myxal]

What magic mushrooms are in that new formula that 409C crude doesn't (reliably) boil to petrol anymore? Both of my petro-wells got borked, as superheated crude prioritizes heat exchange with the coldest thing around over flashing to petrol now. 😭

Spoiler

petro well 5k rev C.sav

EDIT: Model 4000 is unsalvageable, model 5000 will receive a mandatory service bulletin shortly.

Edited April 4 by myxal

[Tigin]

5 hours ago, myxal said:

What magic mushrooms are in that new formula that 409C crude doesn't (reliably) boil to petrol anymore? Both of my petro-wells got borked, as superheated crude prioritizes heat exchange with the coldest thing around over flashing to petrol now. 😭

  Reveal hidden contents

 

petro well 5k rev C.sav 1020.84 kB · 0 downloads

EDIT: Model 4000 is unsalvageable, model 5000 will receive a mandatory service bulletin shortly.

There were some sim changes with respect to when the state change is checked:

U57: For each pair of cells: exchange heat, then immediately check both cells for state transitions.

U58: For ALL pairs of cells: exchange heat. Then, for ALL cells: check for state transitions.

State transitions being moved after all heat exchange might explain what you're seeing, although I didn't load up your save file.

 

[myxal]

1 hour ago, Tigin said:

State transitions being moved after all heat exchange might explain what you're seeing, although I didn't load up your save file.

That sounds plausible and I suspected something along those lines. In both builds, the cell where crude appeared was adjacent to ~380C petrol as it was part of the heat exchanger. Oh well, in the 2nd build it's pretty straightforward to trim the heat exchanger a bit to dedicate the top shelf to phase change, keeping it above 403C at all times.

[EricKlei]

On 4/3/2026 at 3:28 AM, sakura_sk said:

Did that sim change also change how doors closing on top of gases/liquids behave? A door closing previously displaced gases or liquids consistently. That doesn't seem to be the case anymore

I don't think displacement changed but there were a number of sim changes and door changes. Could you provide some more information? 

[Vertel]

From what I can tell a side-effect of making airlock tiles close simultaneously has been exposing some underlying randomness in the direction of displacement for the elements inside the airlock. Whereas before the lower tile of the airlock closing first meant there was some consistency you could rely on (upper tile will always displace only to its adjacent tiles when it finished closing after the lower tile), now the entire contents of the airlock displace at once, and not necessarily to its adjacent tile.

In this setup for example multiple cycles of the airlock opening and closing can displace all the gas inside the airlock to the upper tiles, to the lower tiles, to the right tile, or split it between the right and left tile. There's no way to predict or control the displacement, which has negatively affected pretty much every build relying on using airlock displacement.

[HarryMcCleave]

To provide some clarity: the displacement logic has not changed. Doors still displace two tiles, starting with the root cell. The displacement logic in the simulation is also unchanged, what has changed is the timing of when messages are sent to the sim.

Required background: In the sim, when displacing gases or liquids, each neighboring cell is considered as a potential destination and used for the entire displacement if available. The order in which neighboring cells are considered is the same for all displacements within a single sim tick, but rotates each tick (e.g., on frame 0 every displacement checks right first; on frame 1, left first; frame 2: down; frame 3: up; frame 4: right again, and so on).

With automation in U57 set to a cycle length that is a multiple of 800 ms (4 s in Vertel’s example), this allowed displacement to consistently occur on a sim tick with the same directional bias. This is no longer the case in U58.

The property that the “root” of the door displaces before the top remains intact and can still be leveraged for directional liquid displacement. However, builds that relied on very precise automation timings may need to relax their timing tolerances slightly. Builds that functioned as perfect pumps by consistently hitting the desired sim tick will now be less efficient (the root cell is expected to pump “forward” about 50% of the time, while the top cell will still be displaced “forward” 100% of the time).

For those interested, the underlying bug fix addressed doors leaving behind invisible solid tiles while open, which caused doors used to toggle heat transfer in a vacuum to be unreliable. While this was primarily identified as an issue with unpowered doors, it could also occur with powered doors, the root cause was automation timing.

Previously, sim messages could be triggered both by automation changes and by animation-driven state machine transitions. Now, only the state machine drives sim state events. The previous behavior allowed both an “open” and “close” event to be sent to the sim on the same tick. Since the sim processes all messages of one type before another (with “open” processed before “close”), the door would always end up “closed” in the sim if both messages occurred on the same tick, regardless of the order in which the game sent them.

[HarryMcCleave]

I do suspect there is an issue with automation timers that are shorter than the door animations and am looking into that but thought it might be helpful to provide some clarity on what was behind the difference Vertel highlighted.

[zhongmotianqi]

On 2026/4/11 at AM9点23分, HarryMcCleave said:

我怀疑是自动计时器比门动画短的问题，正在调查，但觉得澄清一下Vertel指出的差异背后的原因可能会有帮助。

After the update, the mechanical airlock will not be affected by signals during the switching process. Before the update, if the signal turns red during the opening process, it will immediately close