Stable Build: 41.78.16 | IWBUMS Beta: 41.78.16 | Version history | Wiki
Follow us


News & Dev
July 21, 2022

Liquid Zedball

Haylo survivors.

41.73 STABLE

We have the next patch to the stable branch primed and ready to go, however an issue that our fantastic Unstable beta testers have flagged is keeping it held in its pen for a little longer.

Players reported that some houses they’d cleared were spawning zeds upon booting up the new build, which alerted us to a snag in our map export process not dealing with map boundaries changing with map expansions. All previous map expansions came along with forced save incompatibility so this crept through unnoticed until now.

While it’s an aggravation rather than a save-breaker, we didn’t want to send a build with a known issue out to the masses – and have spent the last few days setting up a fix. This will need some testing, after which we’ll be looking to pump out the latest version next week.

If you’re interested in the changelist, or want to jump in to try it out, then you can find the unstable release notes for 41.72 and 41.73 behind the hotlinks.


One of the focus points of Build 42 is on extended survival in the months and years beyond the initial Knox Event outbreak.

For this, we are revamping our crafting system – and Turbo’s role has been in laying new foundations for a set-up that allows for: crafted items that have more RPG-like variable attributes based on the crafter’s skill, stats of input items that are reflected in the attributes of a final output item, and the ability of the game itself to recognise all these different attributes when an item is being passed between all of its various different locations and systems.

The next stage of this work, meanwhile, has been in taking this same sort of mentality to the liquids in the game – and also making them ever more interesting in our new crafting set-up.


Let’s start with a video, and then move into some explanation.

So what exactly does this mean for the water, paint, gas, alcohol, washing detergent and bleach of the Knox Event?

Essentially all fluids will be defined and stored in a global registry, which is where we as devs can add new vanilla liquids – but also will make the system very moddable.

Each definition will store basic info such as ID, name, colour etc – then has different categories it can belong to like Beverage, Alcoholic, Fuel, Flammable and such. Beyond that we also tie in properties per litre of this particular fluid: for example Carbs, Proteins, Alcohol percentage or Energy if it’s a flammable fuel.

Liquids that are hazardous or poisonous can also have modifiers that configure the maximum poison effect, and how the effect behaves when mixed.

So yes, we’re going to have the most realistic bleach-drinking ever seen in gaming.


Containers are the coding class that actually store the fluids, and are the way in which the game code interacts with the above definitions.

Inventory items, objects found in the world and vehicles will all have a fluid container – which will allow them to store and use the liquids/fuels/whatever that they contain. Each container also has information stored with it that shows what particular fluids have been mixed in, and their content percentages relative to each other.

The system calculates and caches the summary of all the containing fluids properties based on their percentages. So, if you add 80% Soda and 20% pure alcohol the mixture fluid in the container will have 80% of the soda’s carbs, proteins etc and 20% alcohol. Then, when transferred again, the right ratios will still be maintained.


Finally, we hear you cry, cocktail mixing will be a part of the apocalypse!

Yes, but also consider the applications this will bring to post-apocalyptic crafting – as well as to more basic stuff like mixing paints to create different colours, providing different fuels and different ways to tamper with said fuels.

Certain versions of our planned workstations, say one for brewing, could have one or more ‘fluidcontainers’ attached – while also allowing other ingredients as item inputs. Likewise we can have recipes that require more precise mixing and concentrations should we desire it.

The system does retain some control over your George’s Marvellous Medicine creations. We can put limits around what can, and cannot, be mixed – however we’re not 100% on how many limitations we will put on things right now. This will probably come through testing later down the line.

Unrestricted mixing would mean, for example, that any Fluid can be mixed with Fuel, which would mean that the energy value property per litre would go down when mixed, and that anything using the fuel such as a car or generator would have its operation and potential damage governed by the sort of fuel that had been put in.

The ability to recognise tampered fuel, poison etc. would (as usual) be gated behind the game’s professions – so a mechanic might smell something suspicious with watered down gas, or a chef might spot something odd with a mild concentration of something nasty in a bottle of juice.

When it comes to poisonous liquids, each has a maximum effect (mild, medium, severe, deadly etc) and control parameters such as a minimum volume and mix ratio. So, if a poison has max effect ‘deadly’ and the minimum amount required for death is 200ml – and you have 100ml mixed into a bottle – then the final effect when drinking will most likely be a medium poisoning.

The new system will also add new depth to such things as filling up a vehicle with gas, or siphoning gas from a car’s tank – but we’ll also retain the game’s current quick context options like “fill bottle from tap” to keep things speedy.


Domestic and wild animals, albeit with fairly basic AI brains, will also be a part of Build 42 – and we have already shown our cows, sheep and deer. A fairly realistic take on poultry-keeping will also be part of this.

Please note the following UI is super WIP! We may well end up with icons instead of the 3D chickens.

Based on our own experiences with keeping chickens – if you have a henhouse you will have to close its door every night after your brood have gone in to roost. Otherwise there’s a very real chance of Fantastic Mister Fox paying a visit and stealing a few, and potentially leave others dead in their pen.

You’d be advised not to forget to let your hens back out in the morning either – for fear of them losing their condition, and adding to the mess in the henhouse that will need cleaning out.

Hens will also enter the nesting boxes within the henhouse to lay their eggs, and from which you’ll have to collect the eggs on a regular basis – if you haven’t collected recently then hens will choose to lay outside in their pen instead, where there’s an added risk of them being eaten by wild animals or going bad.


While we’re going in DEEP (as is generally our way) on stuff like the above – Build 42 will also feature all manner of other improvements to the game engine, MP systems and general zombie survival and early game stuff too. So don’t fret too much if aspects of the above don’t exactly match your own play-style.

It should also be said that it’s still some ways off – partly because of dev illness (and recovery!) that we’ve discussed before, and partly because a proportion of the team are still maintaining and improving Build 41.

From now on you’ll likely notice the changelist of 41 patches shrink a little, as team members are taken off 41 and plugged into work on features within the 42 matrix.


We are back on the hunt for an Animations Engineer / Technical Wizard  – most likely someone from the AAA game development space who has pines for joining a close-knit team of indie devs. If this is you, or someone you know, then our job page lives here!

This week’s forlorn firemen from OtakuYazawa. A changelist of all our pre-release and post-release patches since the 41 beta began can be found here. The Centralized Block of Italicised Text would like to direct your attention to the PZ Wiki should you feel like editing or amending something, and the PZ Mailing List that can send you update notifications once builds get released. We also live on Twitter right here! Our Discord is open for chat and hijinks too. Experienced games dev and want to work with us? Details here.


41.72 Unstable

News & Dev | 07 July 2022



News & Dev | 04 August 2022
Stable Build: 41.78.16 | IWBUMS Beta: 41.78.16 | Version history | Wiki
Follow us