Nucleares Patch Notes — January 2, 2026
Aggregated from Steam, cross-tracked with Battle.net coverage on GamePatchNote.
A new update is live in Nucleares, and it brings something many of you have been asking for:
Co-Operative Mode, powered by Fusion 2.0. Now entering closed beta testing.
For the first time, multiple operators can work together inside the same reactor.
You can create public or private rooms and run the plant as a team, directly from the control room.
All core systems are available in co-op:
Panels, gauges, regulators, lights, and switches
Shared reactor states and synchronized core visual effects
Real-time interaction between all connected operators
⚠️ About the Co-Op Beta
This mode is currently in closed beta and still experimental.
Expect rough edges, adjustments, and ongoing improvements as we gather feedback and fine-tune the experience.
What Else Is New?
Alongside co-op testing, this update includes several fixes and performance improvements aimed at making the game smoother and more stable:
Better synchronization of core systems and visual effects
Optimized activation of external objects to reduce overhead
Reduced impact from text and water occlusion systems
Improved dynamic lighting performance and stability
Various internal fixes to improve long-session reliability
These changes help prepare the game for the increased load that cooperative play introduces.
V 2.2.25.204:
- Fixed an issue in AO where it triggered false hazard alerts in the condenser.
- Fixed an error in AO pathfinding, where the agent sometimes could not reach certain points.
- Fixed an error in the lighting of the protective suit container, which sometimes turned off depending on the camera angle.
- Fixed the exaggerated silver effect on tree leaves at night.
- Fixed an issue that prevented the evaporator from being analyzed directly from the tablet.
- Fixed an issue with turbine damage textures not being restored after repair.
- Fixed a bug where the balance meter scale color sometimes failed to update.
- Fixed an error in the labels on the fuel bay hatch opening and closing panels.
- Fixed an issue where Russian and Chinese characters appeared as squares in several UI elements, including the ‘Continue Game’ menu, the ‘Loading progress’ message, and the inventory.
- Fixed a bug that caused the saved progress list to remain stuck on the screen if the player clicked on continue progress and then on new game.
- Fixed the flickering in the intensity of the shadows that occurred when going outside.
- Fixed the visual defect that occurred when going up the stairs in the emergency generator room.
- Fixed a bug in the crane, where the clamp would get stuck after releasing a control rod.
- Fixed a visual bug at the base of the reactor vessel where there should not have been water.
- Fixed a bug that caused Geiger counters to spawn infinitely when using the device while the time-acceleration menu was open.
- Fixed a bug that prevented doors from responding correctly when interacted with during their opening or closing animation.
- Fixed syncroscope animation jittering when the turbine was far from synchronization speed.
- Fixed the bug in the fire sprinklers, which did not turn on in certain situations even when there was a fire.
- Fixed the bug when going up the stairs from the mezzanine on the ground floor of the fuel room.
- Fixed the bug in the game settings menu, which did not restore the volumes when canceling changes.
- Fixed an issue where the safety shutters did not restore their open or closed state after loading a saved game.
- Fixed an issue where Level 1 and Level 2 alarms could sometimes keep sounding even after the alarm condition had been resolved.
- Fixed an issue with the core coolant inlet and outlet flow meters, which did not correctly display the actual flow or failed to update when the pumps were not operating.
- Fixed an issue in core temperature calculations above critical levels, which caused sudden drops or oscillations.
- Added an option that allows players to choose any display resolution, even if they aren't verified in-game.
- Added shaking effect to the primary circuit circulation pumps when they are operated under critical conditions.
- Adjusted the sensitivity of the NO RESISTOR BANKS alarm so that it does not sound when there is an increase in demand.
- Adjusted the design of the game's options menu to unify criteria across options and improve readability.
- Adjusted the capacity of the pressurizer's vent valve to prevent a sudden drop in internal pressure.
- Formatted credit amounts to display in currency format.
- Improved the credit payment message for clearer information on the due date and default status.
- Improved the wet effect on the exterior when it is raining.
- Improved core moderation modeling: coolant fill level now affects neutron moderation more realistically, with a sharper loss of moderation at low core water levels.
- Improved fuel temperature accumulation: heat buildup now reflects reduced cooling and decay heat effects, increasing core damage risk when coolant levels are insufficient.
- Optimized external object activation when going outside to reduce performance impact.
- Optimized on-screen text to reduce resource consumption.
- Optimized simulated water occlusion to reduce resource consumption.
- Optimized the overall control of dynamic lighting.
- Optimized the transition of dynamic lighting, including intensity, activation, and interaction with volumetric lighting.
- New tree assets with higher quality and better performance.
- The Dyatlov Spirit option was exposed in the AO settings (now disabled by default), because AO commentary was sometimes confusing for players.
- The minigames were reinstated for special dates, starting with Christmas.
Cooperative mode: Fusion 2.0 Implementation \
- Can create rooms (public or private).
- Fully operate the reactor from the control room.
- All panels, monitors, lights, gauges, regulators, and switches are working.
- Core visual effects were synchronized.
Pending Co-op Mode Issues:
- Clients can’t see or operate AO or the crane.
- Clients can’t use the tablet.
- Clients aren’t fully animated yet.
- Clients can’t handle objects.
- Not all visual effects are synchronized.