Prehistoric Kingdom Patch Notes — June 10, 2026
Aggregated from Steam, cross-tracked with Battle.net coverage on GamePatchNote.
This PTB release introduces Animal Combat, an all-new emergent gameplay system that allows your animals to react more dynamically to their environment and to one another.
While this feature is still a work in progress, we're eager to hear your feedback. In particular, we're looking for reports on animal responsiveness, aggression behaviors, and any unexpected interactions you encounter as we continue expanding combat mechanics, refining animations, and balancing behavior.
We've also made significant strides in stability and optimization. Overall CPU and rendering performance have improved since the previous update, making it easier to run and manage larger, more complex parks.
Please note that Allosaurus and Pachycephalosaurus are NOT in this game version, and will instead be released with the full, live update!
Thank you for helping us test and shape the future of the game!
PTB Features
Animal Combat
Animals can now fight one another through a fully dynamic combat system. Each species has a combat profile that determines how it behaves when confronted by rivals, predators, or prey.
Animals assess threats and opportunities in real time, choosing whether to stand their ground, intimidate an opponent, pursue a target, or retreat from danger. These decisions are driven by situational awareness, with creatures weighing factors such as confidence, opponent strength, and the risks of continuing a fight.
When tensions escalate, encounters can develop into full combat events involving multiple participants. Animals may circle opponents, threaten, bluff charge, lunge, bite, kick, tail swipe, and utilize other species-specific attacks against their targets.
Battles have meaningful consequences! Successful attacks inflict injuries, with the damage determined by the attacker’s strength and lethality, as well as the defender’s resilience. Particularly powerful blows may even knock an animal to the ground. Similarly, fleeing animals also have a small chance to stumble, based on their overall wellness and fatigue.
If an animal survives its injuries, wounds will gradually heal over time, leaving behind unique scars that persist on an individual basis.
The system’s effects extend beyond the battlefield. Victories and defeats can influence herd hierarchies, leadership roles, and ultimately an animal’s chances of survival, helping create unpredictable and emergent wildlife interactions across your parks.
Improved Animal Locomotion
Animal movement has received a substantial overhaul, making locomotion feel more natural, responsive and believable across a wide range of situations. Animals now preserve momentum more effectively while turning, directly leaning into their turns if they are tight enough.
Animation blending and movement control have been significantly improved, allowing animals to transition more naturally between behavioral states while reducing sudden directional changes. The results are especially evident in larger species, which now exhibit a more convincing sense of mass, momentum, and stability during movement.
Animal Carcasses and Decomposition
Dead animals now count as carcasses and can provide nourishment for carnivores, having maximum feeding capacity. Dead animals can also act as vectors for disease, with certain afflictions spreading more effectively through scavenging behavior.
Carcasses will decay over time, featuring a decomposition visual overlay, before eventually disappearing entirely.
PTB Changes
Overhauled Save & Load Menus
The Save and Load menus have been overhauled with a fresh design to show your statistics and PTB saves. There are also more differences between the two menus, so you should be less likely to accidentally load instead of saving a park.
How to Access the Public Testing Branch (Experimental!)
Right click Prehistoric Kingdom in your Steam Library
Go to Properties
Betas
Select 'ptb_public_testing'
Please note that it is not recommended to play Public Testing Branch parks on earlier versions of the game. Please send feedback and bug reports to our Discord server's appropriate channel.
Known Issues & Additional Notes
Some of the newly-added AI complexity has exposed new cracks in animal AI states execution. That is to say, we're aware of potential issues causing animals to get soft-locked into their current state. Whenever this occurs, please report the issue, attaching a screenshot of the animal's AI brain (accessible by pressing Shift+B during selection)
Several combat states are currently under various degrees of completion, with polishing expected to be occurring all throughout the PTB period:
Hunting is currently in the middle of being implemented, so you may find unexpected hunting behavior. Prey targeting is not incredibly selective at the moment, and predation behavior overwhelms predators' feeding choices. This will be tuned as we continue to work for the update's live release.
Some animals can move faster than we would like during combat encounters, especially younger individuals
Animal circle states and some attacks result in more or less clipping - we are going to do our best to reduce this as much as possible, though the dynamic nature of the combat system entails it will never be resolved in all capacities
Significant amounts of animal combat can seriously degrade AI performance. This is an area we are currently optimizing
Several animals are still missing their full combat capabilities, currently being unable to attack. These animals are Muttaburrasaurus, Ouranosaurus, Psittacosaurus, Dryosaurus and Leaellynasaura.
Much of the audio implementation for combat audio events, as well as combat music is currently unfinished, and actively being worked on. We expect the audio library for animal attacks and reactions to be expanded as PTB continues
Some recent data misalignment has caused some animals' swimming capabilities to regress, causing surface positioning to be offset, often pushing individuals under water. We'll be fixing this soon
Full Patch Notes
Additions
Animals
The following animals will now sneeze when sick:
Nasutoceratops
Pachyrhinosaurus
Protoceratops
Triceratops
Brontosaurus/Apatosaurus
Tyrannosaurus
Animals will now actively update their locomotion style based on their current stamina, which will result in tired animals not being able to run
Animal carcasses can now act as food sources, decompose, and transmit diseases
Animals will now lose Safety need when they perceive danger or are engaged in combat
UI/UX
Added Paleopedia descriptions to the following taxa:
Stegosaurus ungulatus
Tarbosaurus
Added Paleopedia descriptions to the following excavation sites:
Nemegt Formation
Added a new error tooltip when placing a Vivarium animal in an incompatible vivarium: Incompatible Vivarium Configuration!
Added a Stamina bar to the Animal Info Menu
The Animal Info Menu will now report more carcass-specific data for dead animals, such as decomposition state and meat quantity
Added Paleopedia information for animal Confidence, Temperament, and Niche. This can be found in the Social tab
Rendering
Added a Motion Blur feature to the game’s screen effects. This is disabled by default and can be enabled under the ‘Screen Effects’ section in the Options Menu
The map edges now have a visual boundary overlay, which is highlighted and grows in intensity during placement actions. This should better allow users to understand where the bounds of the editable map lay, and will allow us to create custom bounds in the future
Audio
Added additional angry vocal variations to Triceratops and Tyrannosaurus
Added an alternate notification sound for when an animal dies
Changes
Balance
Added Stegosaurus ungulatus to the Lourinha Formation
Animals
Animals can now no longer be moved if they are dead or engaged in combat. This limit is removed in Sandbox mode
Made significant improvements to animal<->animal avoidance, with pathing being much more aware and responsive to other individuals. This should reduce some instances of animals walking through each other
Main animal welfare now takes Hitpoints and Wellness into account
Stamina drain for animals is now driven by exact moment-to-moment locomotion speed, not the desired speed. Animals should become exhausted less quickly during specific actions
Animals “Anger” behavior is now driven by environmental and emotional needs, not including hunger or thirst
Actions like eating and drinking can now be quickly interrupted by aggression and danger
Animal carcasses now disappear after a duration proportional to their size classification
Animals who are occupied, such as held by the player, in quarantine, or in combat, are now considered to be unavailable to social and family group behavior. The next highest member will be able to step in as the interim leader to coordinate herd movements
Adjusted drinking intakes for all infant animals, lowering their drinking duration times across the board
Adjusted vision ranges for all animals, bringing most smaller animals up, while slightly reducing the range of the largest animals
For aggression targeting, animals are now considered to share a social group if their current family group leader shares the social group
Dead animals will now not count towards enclosure welfare analysis
Corrected oversizing mistakes in both Triceratops species and Pachyrhinosaurus canadensis
Play/Chasing behaviour is more refined and consistent
Updated sprinting speeds for Tyrannosaurus and all hadrosaurs
Animals can now trip when fleeing, with a greater chance depending on health and fatigue
Construction
Reduced input jitter across all actions
Action input while the cursor is overlapping the GUI has been overhauled, with any of the actions snapping the placement cursor to the middle of the screen when players are interacting with the game’s UI. This should improve visual feedback for elements which have not been placed yet
Gave modular construction a fresh batch of improvements and features aimed at generally improving the quality of life of the building experience:
Vertical shifting has been re-worked to better support aligning. When stacking and aligning are enabled, holding LeftShift will now activate the vertical offset along the hit-aligned direction of the current piece, instead of simply going up-down. This should ultimately facilitate sinking pieces into each other, or raising them along specific directions
The piece rotation snap hotkey was changed over to LeftControl from LeftShift so it would not collide with the vertical shifting feature. Holding LeftControl while pressing either of the rotation keys will now snap the piece 45 degrees along its up axis
Turning off object aligning will now reset the piece’s rotation
Hovered pieces within modular editing will now be highlighted
Improved fence placement and modular interaction with fences
Curved sections that are started off of existing posts or barriers will now more smartly switch their starting vectors based on the players’ input
Adjusted fence snapping logic for modular pieces that snap to fences, so that invalid fence slopes would be given appropriate feedback
Improved visual and audio feedback around fence replacement
Environment
Made Tropical lighting slightly more consistent with temperate
Foliage
Removed shine from distant foliage impostors for a smoother appearance
UI/UX
Improved camera orbiting accuracy, basing the dynamic adapting logic on modular and terrain sampling, rather than terrain sampling alone. This change should improve controls around structures that are farther away from the ground
Added many camera improvements when switching from and to tracking mode, overall improving the camera view’s stability and reducing jumpiness
State icons will now disappear after about 30 seconds so that numerous issues wouldn’t clutter the screen. Opening the park issues menu will instead display all the state icons for the various issues
Updating tracking functionality across all Info Menus:
Tracking is respected by players setting tracking preferences through clicking the toggle
Tracking is forced on when an object is selected through a third-party UI (like notifications, or park issues). This enforces camera vision over the object
Tracking is also enforced when re-selecting an already selected object
The tracking preferences are now persistent across sessions
Improved GUI slider controls
Previewed animals within the Nursery Menu will now smoothly transition their walk animation based on current maturity
‘Dying Animal’ park issues are now only generated after an animal falls below 70% wellness
Opening the Landscaping Menu now clears modular editing as well as modular actions
Rendering
Targeted several image stability measures in order to reduce overall noise and muddiness:
Frustum shadows begin fading into the image at a much higher distance, with the shadows now relying entirely on physically-based casting at a close and medium distance. This effectively removes a layer of shadow artifacts
Smoothed edges of cast shadows, especially at lower visual settings. This aims to improve image clarity all while increasing fidelity for all users
Improved shadow culling, with shadows at the edge of the screen now being much more stable
Slightly increased object rendering distances across all visual settings
Reduced detail ambient occlusion on Cinematic, Ultra and High for a less dirty look
Audio
Animals dying or having diseases discovered will no longer trigger a park issue sound
Lowered mid-frequencies on animal hover sound
Bug Fixes
Crashes
Fixed a rare crash when special modular pieces check their nav connectivity
Critical
Solidified Steam Workshop checks so that Workshop content would be available while playing debug builds on the Public Testing Branch
Fixed a critical rare desync that could occur downstream of selling animals that likely lead to unwanted animal teleport behaviour, including incorrect animals being moved to quarantine
Vivariums
Fixed several deep system desyncs that could cause Vivarium loading to generate the incorrect enrichment configuration. Among other problems, this could cause floating vivarium animals
Fixed a critical logic mistake that would cause Vivarium environments to incorrectly refresh when a burrowing animal was added to a terrestrial Vivarium
Fixed a significant number of audio event leaks that could leak to audio system instabilities and degraded performance
Fixed a memory leak in interactable <-> navmesh mapping
Fixed path system leaks that could destabilize the entire navigation system after a long period of time
Gameplay
Fixed a starting configuration issue in the ‘Rockies’ map that would cause the Visitor Spawner facility to be obstructed, preventing visitors from entering the park
Fixed a selection issue that could cause modular selection and group editing implicitly, even if the cursor was hovering an animal target
Tightened up modular refund logic. Switching modular interchange sets (such as Vivariums’ layouts) no longer triggers a refund money glitch
Animals
General improvements to Animal AI stability
Fixed a bug that prevented animals from properly avoiding each other
Fixed a locomotion issue that caused animals speeds to disrespect their original animations. If you notice any major discrepancies compared to the previous version, please let us know
Fixed a number of animal animation oversights:
Fixed adult Muttaburrasaurus not using their trot animation
Fixed baby Panthera locomotion transition offset
Fixed baby Ursus not strafing left properly
Fixed a few instances of bad animal growth data, causing specific body parts to not play the correct animations. This could result in forelimbs clipping into the floor plane, for instance
Fixed idle animation transition issue for the amphibious Titanoboa
Fixed many instances of bad animal IK settings causing animal limbs to stretch out during certain animations
Fleeing animals no longer have to stop at midpoints along their direction of travel
Animals now use animation-derived data to better position themselves when eating, drinking, and interacting with objects
Fixed animal locomotion getting caught on corners in some cases
Fixed inconsistencies that could prevent animals from drinking in certain circumstances
When finding a place to stand for interaction, animals should now reject positions that are far too high or low
Fixed a bug in the grounding logic that could cause quickly turning animals to tilt dramatically in incorrect directions
Fixed bugs in the awareness system that could reduce the consistency of animal vision
Staff
Fixed a staff gate bug that has been allowing staff to reach rooftops
Fixed shoveling instability at high game speeds
Buildings & Scenery
Fixed animal info sign loading
Construction
Fixed rare race condition causing modular pieces to not restore their correct layers if placement was done too quickly. This could cause the affected pieces to not interact with entity navigation, also becoming unselectable
Fixed bugs in terraforming that could cause inconsistencies after edits
UI/UX
Fixed several issues related to game view snapshot functionality:
Prefab previews and save snapshots should now have correct post processing
Auto-save previews should not be black anymore
Resolved flickering in the Animals Management Menu list
The ‘Allow unassigned staff’ toggle in the workzone info menu settings should now persist correctly
Fix for a long-standing issue where the animal social GUI could report a completely wrong animal as the group's leader, even a different species
Fixed certain button interactions not triggering audio in the Main Menu
Fixed a nursery menu animal preview animation issue that could cause vivarium animals to freeze their animations after a new incubation was started
Fixed a one-frame lighting glitch that would occur when opening the Management Menu
Tightened up tooltip logic so that tooltips getting stuck on screen wouldn’t happen anymore
Unified animal pregnancy display logic
Fixed animal state description reporting an animal as ‘Dead’ when it was actually collapsed
Fixed a notification system threading error that caused certain notifications not to trigger anymore (such as the animal pregnancy notification)
Fixed a critical bug that could result in the Animal Info GUI individual switching to completely break down
Fixed ‘Hard Difficulty’ text spelling
Rendering
Improved water rendering visuals
Performance
Patched a major performance degradation issue related to modular construction which could irreversibly lower framerate baseline within a session. You should now be able to play much longer at a stable FPS
Significant animal animation performance improvements (largest CPU bottleneck for parks with many animals)
Core logic pass is ~25% faster
Animal animation controller passes are nearly twice as fast
Improved shadow rendering performance for all game settings by balancing shadow distance
Improved Animal AI Multi-Threading
Made decent performance improvements during modular structure placement, especially noticeable for large groups with many pieces
Optimized state icon processing
Continuous animal visual updates are more efficient