Prehistoric Kingdom Patch Notes — March 19, 2026
Aggregated from Steam, cross-tracked with Battle.net coverage on GamePatchNote.
Welcome, Park Managers!
This surprise bug-fix patch for Update 16 aims to address some of the most commonly reported balancing problems related to the animal disease system, while resolving numerous stability issues, such as memory leaks and crashes. In addition, this update introduces new vivarium animal animations - most notably full aquatic support for Titanoboa, which can now be housed in the Amphibious Vivarium.
Please enjoy the improved experience while we continue to work on Update 17, which will be introducing new animal species, animal combat, overhauled management systems, and many additional optimizations!
Disease Balance PSA
Recommended Experience
The latest disease balance changes are best experienced in a NEW GAME of Challenge Mode! On average, it takes around 1 year of in-game time before diseases start to become more common.
The immunity of an animal is now also modulated by its current age, with players making use of supplements and era-appropriate plants (for herbivores) to improve their animal's overall immunity. Selecting an animal and hovering over its immunity stat will provide a detailed readout of all the factors currently impacting it.
Existing Saves Warning
If you load an existing save, your animals may already host a variety of incubating diseases from the original Update 16 release, leading to an inaccurate gameplay experience. Animals with old age are also much more susceptible to death, so players may see a mass-dying as a result.
For the full list of changes, please read the patch notes below.
How to Access the Public Testing Branch (Experimental!)
The Public Testing Branch (PTB) is a version of Prehistoric Kingdom that can be opted-into on Steam, containing experimental and potentially breaking changes. With the help of the community, we're able to hunt down various issues and gather feedback before pushing a an update to the public version of Prehistoric Kingdom.
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
Please send feedback and bug reports to our Discord server's appropriate channel.
As a result of FSR, humans can appear smeared in motion. Turning off FSR will resolve this issue.
Sometimes when going to refill a vivarium, staff will run in a straight line through EVERYTHING.
Keepers will sometimes walk on the spot when trying to clean poo. It's important that they get their steps in.
NOTE: The animation preview dropdown in the Nursery does not yet function for vivarium species.
NOTE: Due to the sheer workload of animations, the majority of animal knockdowns are missing audio.
NOTE: Vet-related animations do not have audio yet.
Full Patch Notes
Additions
Animals
Titanoboa can now be housed in the Amphibious Vivarium
Added new idle and locomotion animations to:
Titanoboa
Diplocaulus
Tiktaalik
Simosuchus
Diictodon
Buildings & Scenery
Water volumes for Amphibious Vivariums can now be switched between Clear and Tannin through the customization tab of the Vivarium widget
Audio
Added missing Nigel lines for Sahonachelys
UI/UX
Added percent status labels to various places within the GUI that should better report at which stage of treatment various animal afflictions are in
Changes
Animals
Slightly lowered feed consumption for Vivarium animals across the board
In an effort to improve readability and flow for the animal disease system, we took many balancing measures:
Reduced overall spawn rates for all afflictions across the board
Added a 'Max Immunity' read-out to the Nursery Menu animal preview
Animals with Slow and Realistic growth speeds now share the same starting immunity
Massively decreased treatment times for all affliction types
Increased symptom severity for all illnesses, which should hopefully better telegraph current issues with an animal's health
Individual animal's immunity now has a deeper impact on disease progression and health drain, with the immunity scaling more biologically accurately to an animal's age: mature animals have higher immunity than younger individuals, which themselves have higher immunity than elderly individuals. Among other things, this should result in older animals having a much harder time recovering from illness
Updated descriptions for most illnesses in an attempt to give out more accurate information that would be better tied to the various gameplay systems
It is now easier for feeders and troughs to contract diseases from infected animals. Healthy animals that eat and drink will also now lower the cleanliness of these modules, modulated by the current dirtiness of a habitat
Staff
Vets will now not survey animals that are in quarantine or dead
Buildings & Scenery
Modules such as feeders and water troughs can now be contaminated by transmissible pathogens without having to be dirty. Previously they required 10% dirtiness, which practically made it so these modules could never actually be contaminated
Feeders, enrichment feeders and water troughs lose a little bit of cleanliness when used by animals
UI/UX
The Animal Info Menu now displays recovery progress for each present affliction
Overhauled state icon readability - they are now overall smaller on screen, display screen-space angular stability and are sorted by distance
After some reported player confusion, we disabled session persistence for the 'Vivarium' filtering option in the Nursery Menu
Audio
When the camera is above ground-level, animal sounds become less attenuated to better serve the top-down gameplay (excludes sauropod calls)
Bug Fixes
Critical
Patched a few AI navigation locks that could result in crashing
Improved general stability around undo/redo
Fixed a Vivarium loading bug which would affect Terrestrial Vivariums with a burrow-substrate and would cause plants to reset and the enrichment items to desync
Fixed a Vivarium loading bug which could cause saved enrichment items to persist within the structure, even if toggled away through the GUI
Animals
Fixed many issues resulting in animals often failing to drink from painted water bodies
Fixed a few instabilities in the animal animation systems which could cause certain animation states to be stuck
Patched a couple of exceptions in the Vivarium animal animation system that could cause their animations to glitch out
Buildings & Scenery
Vivarium wall claddings have fixed collision, improving selection responsiveness and entity navigability with respect to vivarium structures
UI/UX
Fixed at least 2 bugs that could occur when generating the animal list in the Animal Management Menu. This should resolve some instances of the list having incorrect layout or reporting overlapping activities for certain animals
Fixed the 'Move' button in the quarantine bay widget not triggering the animal discharging action
Fixed enrichment feeders not displaying supplement controls when selected
Fixed a logical error that could cause certain afflictions to be labeled as 'Treatable' in the Animal Info Menu when they are in fact not treatable
Fixed a searching issue in the Building Menu that could cause certain items to be loaded into the results twice
Fixed a few instances of desync between Vivariums and Animal Info Signs, making sign species selection much more responsive to Vivarium animal stock changes
Rendering
Fixed data issues causing water volumes in Amphibious Vivariums to be visually glitchy when viewed from the sides
Audio
Patched some bugs in animal audio processing
Fixed an audio oversight that could cause vivarium animals' breathing to be heard even after they would cease existing
Fixed an issue that caused high elevation wind sounds to play all the time
Performance
Took an in-depth look at memory stability, having fixed dozens of memory leaks, especially in the pathfinding and animal systems. This should hopefully reduce the amount of crashing, though GPU memory usage continues to be high. This will be addressed more in Update 17.
Resolved memory leaks in the terraforming system - this could cause some of the reported FPS drops related to terrain actions.
Made many small CPU optimizations to peripheral systems.