Hello Survivors! We’re back, and we have a new update, which is now available to play and test on the Unstable branch on Steam.

As our first incremental update post-Build 42, this update contains fixes and updates for a whole bunch of things, and we’d love your feedback on them.

How to update your Project Zomboid game client to access Unstable

1. Right-click Project Zomboid in your Steam Library.
2. Select “Properties”.
3. Under “Game Versions & Betas” select “Unstable”.

Existing savegames on Build 42.20.4 should not be affected by this update, however, if you want to test 42.21 with an existing save, we highly recommend manually backing up your save before attempting to play it on the Unstable branch.

If you do discover issues with an existing savegame, please let us know via the forums.

What’s in this update?

42.21 is an incremental update and has a lot of fixes, but also a few gameplay improvements. These are relatively minor, but hopefully will improve your “quality of survival” in your personal zombie apocalypse. Below are some highlights; for a complete set of changes and fixes, check out the full update notes on our forums.

Big Ticket Items

Fix: As many will know, we had an issue in which zombies would disappear after a player left and re-entered a “chunk” of the game world; this was particularly obvious in larger zombie population games and as such impacted a lot of our hardcore players. This has now been fixed in both SP and MP. It was a tricky fix for us to pin down and remedy at its root, but is now ready to face the hordes via the Unstable branch.

Fix: Issues of zombie duplication in MP have also been tackled, and we’d ask you to be on the look out for any other instances you spot once Unstable is live.

Updated: A common piece of feedback since the launch of B42 Stable has been the new ‘XXL trees’ occasionally getting in the way of the player – especially when driving. 42.21 contains changes to the XXL tree cutaway behaviour: they now cutaway better for players in vehicles, they no longer hide houses and furniture they overhang, and their overall transparency has been adjusted for better overall visibility. We’d love to hear your feedback on the tweaks; we regard this as a work in progress.

Re-enabled: In our 42.20.4 Stable hotfix, the “loadstring” and “loadstream” commands were disabled to help address security vulnerabilities. After investigating further into the security issue, we’ve decided to re-enable those commands. Sorry for the disruption, modders/server admins!

Other Changes

• Characters will now automatically re-equip items after exercise
• Updated in-game player map, to remove inaccuracies while exploring
• Updated localization system to enable more translatable strings
• Updated UI “Spawn Point Selection” preview videos to match Map Glowup
• Added a notification for players who try to connect to an MP server with different game version
• Improved player pathfinding to avoid trampling farming plants where possible

Balance

• Characters with the Welder occupation will now start the game with Welding recipes, instead of Blacksmithing recipes
• Many more (86!) fluid containers can now be used to purify water in the appropriate oven type
• Washing machines will now clean dirty rags, strips, or bandages
• Fridges and freezers will now warm gradually on the day the power goes out
• Refrigeration is now applied correctly to food items in a bag in a fridge or freezer
• Antibiotics can now be packaged using the “pack in box” crafting recipe
• Subbiomes on the map now won’t generate trees on dirt
• Increased brightness on several lamp/illuminated tiles
• Floorboard stash containers found using annotated maps are now more appropriately named
• Explosives will now work in basements (!)

Split-Screen Improvements

Our split-screen audience is small, but it is also mighty – and as such we have polished up some of the more pressing issues within same-screen play. Notably; read book statuses and XP boosts are no longer shared incorrectly, fishing now operates as you might expect, and a notable crash when you shared a moving vehicle with your significant other has been addressed. There are a few more minor fixes included too.

Multiplayer

Expanded anti-cheat system
• Various new cheats now guarded against
• Safehouse exploits remedied

Server browser
• Server Update will display the last wipe, not the last restart
• “Connect” is now disabled when no server is selected

Steam Authentication Exploit
• Fixed an issue where players could enter dedicated servers without correctly authenticating via • Steam, which prevented SteamID bans

Other notable fixes
• Fixed issues when driving with high ping (~150+) so instances of the map not loading in front of the car, passenger teleportation and general MP-associated juddering will be improved
• Fixed a Z-level desync issue, which will better synchronise player coordinates

Plus many and various other MP fixes related to desync, animations, sounds and more.

Unstable testing schedule

We’re deploying this update to Unstable to allow you to test it and give us feedback on the changes. Depending on that feedback, we may do some more tweaking before we deploy to Stable, and may deploy another update to Unstable for more feedback.

Going forward, this should be the standard procedure for all releases; a new update goes to Unstable, it’s tested by you, we potentially make more changes, and ultimately the release goes to Stable, or ‘live’ if you prefer.

The length of time between an Unstable update and a Stable release will vary depending on the complexity of the update, but overall we’re trying to move faster, with Unstable not acting as an “unofficial Stable”, but instead being used for testing and feedback.

Got feedback? Found a bug?

If you’d like to give us feedback on the Unstable 42.21 update, feel free to do so via the Indie Stone forums.

If you find a bug, please read this first, then post the bug in the forums. Please note if you post bug reports anywhere else – especially via Discord – then your report will likely get lost and may not be investigated.

The Block of Italicised Text would like to direct your attention to the PZ Wiki should you feel like editing or amending something. You can also find us on Bluesky, on our Discord, Reddit and Forums. If you fancy, sign up to receive PZ blogs like this in your email right here.

As always, discussions regarding this update can be found pinned to the Project Zomboid Discussions Forums here.