Zombie Respawn Be Gone: PZ Survival Hack

Zombie Respawn Be Gone: PZ Survival Hack

How to Disable Zombie Respawn

Project Zomboid (Build 41 & 42)

Updated for Build 42
No Visual Mods Required
Single & Multiplayer

Quick Start: No-Respawn in 30 Seconds

  1. Start a Custom Sandbox game. From the main menu, select Solo → Custom Sandbox (or configure your server's sandbox settings). For multiplayer servers, see our server admin guide.
  2. Open Advanced Zombie Options. After choosing a spawn location, click the Advanced Zombie Options tab.
  3. Set Respawn Hours to 0. This tells the game that zero hours need to pass for a respawn – effectively disabling it.
  4. [Optional] Turn off migration. Set Redistribute Hours to 0 as well if you don't want zombies migrating into cleared areas.
  5. Start your game. Enjoy a world where once you clear a town, it stays clear (mostly – see Zombie Migration below).

Multiplayer: Already have a server running? As the admin, open the Admin Panel (bottom-right icon) → Sandbox Options, and adjust the settings there, just like above, then hit Apply. Restart the server to apply changes. Need admin commands? Check our admin command guide.

Understanding Zombie Respawn Mechanics

Before turning off respawns, it helps to understand what we're disabling. Project Zomboid uses a respawn system to repopulate areas with zombies over time. In Build 41, by default 10% of a cell's zombie population will respawn every 72 hours. In other words, if you clear a neighborhood of 100 zombies, about 10 will "magically" reappear after three in-game days (assuming you haven't been around).

Default Respawn Mechanics (Build 41)

The game divides the map into "cells" (~300x300 tiles each). By default:

  • Respawn Hours = 72 (3 days)
  • Respawn Multiplier = 0.1 (10%)
  • Respawn Unseen Hours = 16 (cell must be unseen for 16 hours first)

What Changed in Build 42?

Build 42 (unstable as of late 2024) introduced substantial changes:

  • Zombie Distribution Heatmap – New system that makes zombies flow into cleared areas much faster and in greater numbers.
  • Increased Rally Group Size – Default horde size increased from 20 to 50, meaning larger groups migrate together.
  • More Aggressive Migration – Zombies from nearby cells quickly drift into any vacuum you create, sometimes within hours.

Bug Alert (B42 Unstable)

Early B42 builds launched with a glitch: changing zombie spawn settings in sandbox caused spawn count to max out instead. The workaround was to leave settings at default, start the game, then use a mod to adjust afterward. Later patches have addressed many spawn issues.

Single-Player: Making Zombies Stay Dead

New Game Setup - Disable Respawn via Sandbox Options

  1. Select "Custom Sandbox"

    From the main menu, click Solo, pick any spawn location, then choose Custom Sandbox as the playstyle.

  2. Go to Advanced Zombie Options

    Click through the tabs on the left until you see Advanced Zombie Options (it's the last tab).

  3. Set Respawn Hours to 0

    Find the setting labeled "Respawn Hours" (default is 72 hours). Change that value to 0. This tells the game that zero hours must pass before zombies respawn, effectively disabling respawn completely.

  4. Set Respawn Unseen Hours to 0 (optional)

    To be safe, you can set this to 0 as well, but with Respawn Hours at 0, no respawns will happen regardless.

  5. [Optional] Set Respawn Multiplier to 0.0

    This is the percentage of zombies that respawn each cycle. With Respawn Hours = 0, this is moot but setting it to 0.0 won't hurt.

  6. [Optional] Set Redistribute Hours to 0

    This prevents zombies from automatically moving to fill empty areas. If you want no new zombies, period in a cleared area, set this to 0 as well.

Advanced Zombie Options Screenshot
Sandbox Settings - Set "Respawn Hours" to 0 to disable zombie respawn

Peak Day Consideration

Even with respawn off, if your Population Peak Day is in the future (default Day 28) and your Peak Multiplier is higher than your Start Multiplier, the game will continue spawning new zombies each day until it reaches the peak. For a truly finite zombie count from day one, set Peak Day = 1 or make Start Multiplier equal to Peak Multiplier.

Disabling Respawn in an Ongoing Save

Already started a game and want to turn off respawn? You have two options:

Option 1: Use the "Change Sandbox Options" mod

The Change Sandbox Options mod allows you to tweak sandbox settings on the fly in any single-player game:

  1. Install the mod from the Steam Workshop (Workshop ID: 2670674997)
  2. Load your save with the mod active (Load → select save → More... → Choose Mods)
  3. Press the `[` key in-game to access sandbox settings
  4. Navigate to Advanced Zombie Options and set Respawn Hours to 0
  5. Save and restart your game for changes to fully apply

Option 2: Manual edit (advanced users)

If you prefer not to use mods, you can manually edit your save's sandbox file:

  1. Find your save's folder under Zomboid/Saves/<gamemode>/<SaveName>
  2. Make a backup of this folder in case something goes wrong
  3. Locate SandboxVars.lua and open it with a text editor
  4. Find and change these values:
    SandboxVars = { ... RespawnHours = 0, RespawnUnseenHours = 0, RespawnMultiplier = 0.0, RedistributeHours = 0, ... }
  5. Save the file and load your game
Editing save files can be risky. A typo could break your save, so always make backups!

Multiplayer: Server Settings for No-Respawn

Hosted Server (Co-op) – Setting No Respawn

If you're using the in-game Host option to play with friends:

When Creating the Server

  1. After clicking Host, set up a server settings preset
  2. Go through the sandbox options to Advanced Zombie Options
  3. Set Respawn Hours = 0 just like in single-player
  4. Save the preset and launch the server

For an Existing Hosted Server

  1. On the main menu, hit Host
  2. Select your server settings file and click Edit Settings
  3. Navigate to Advanced Zombie Options and set Respawn Hours = 0
  4. Save, then restart the server for changes to apply

Dedicated Server – Config Files Method

For dedicated servers (when you run the Project Zomboid server separately):

  1. Locate the SandboxVars file

    In the server's installation directory, find <ServerName>_SandboxVars.lua (by default, servertest_SandboxVars.lua)

  2. Edit the respawn settings
    RespawnHours = 0, RespawnUnseenHours = 0, RespawnMultiplier = 0.0, RedistributeHours = 0,

    Ensure commas and syntax are correct. Setting RespawnHours = 0 is the key to disable respawn.

  3. Save changes and restart the server

    It's crucial to restart because the server reads those files on startup. In a console you can use the quit command to gracefully save and stop the server.

Admin In-Game Method

If you have a dedicated server running and want to change respawn settings without editing files manually:

  1. Gain admin access

    Type /admin <password> in chat or use the server console: setaccesslevel "YourUsername" admin

  2. Open Admin Panel → Sandbox Options

    Click the admin icon (red button or skull icon) on the UI and choose Sandbox Options

  3. Change the values

    Go to Advanced Zombie Options, set Respawn Hours to 0 (and others as needed)

  4. Apply Changes

    Click Apply or Save. The server will broadcast that settings have been changed

  5. Restart the server

    For changes to fully take effect, stop and start the server

Admin Panel Navigation
Admin Panel with Sandbox Options button

Advanced Tweaks & Troubleshooting

Zombie Migration vs. Respawn

Even with Respawn off, zombies can move between areas. This is controlled by the Redistribute Hours setting:

Understanding Migration

By default, every 12 hours, zombies in densely populated parts of a cell may drift toward less populated parts. If you cleared a parking lot, zombies from the next street might wander over. They didn't respawn – they walked there. Set Redistribute Hours = 0 to stop this automatic migration.

"I turned respawn off, why do I see new zombies?"

Aside from migration, there are a few reasons you might still see zombies after clearing an area:

Initial Spawning in New Areas

Project Zomboid spawns zombies as you explore new areas for the first time. If you clear your town then visit a new place, you'll encounter zombies – not because they respawned, but because that cell is being loaded for the first time.

Meta Events Drawing Zombies

The helicopter event (if enabled) can drag hordes from far away. Fire alarms, distant screams, thunder – these can all cause movement. With respawn off, the total count doesn't increase, but zombies may redistribute.

Peak Population Spawns

If it hasn't reached Peak Day yet, the game might still be adding zombies to meet the target peak population. Once past peak day (or if peak pop == start pop), this won't happen.

Server Config Issues

If on a server you still see obvious respawning, double-check server settings. Sometimes admins forget to edit both files, or a typo means the server fell back to default. Verify by loading sandbox options in-game as admin.

Living in a World with No Respawns

Is Turning Off Respawns Cheating or Bad?

Some purists argue that disabling respawns makes the game too easy – you could theoretically clear the entire map if you lived long enough. Others say it's more realistic and satisfying – after all, in a real apocalypse, once you've killed zombies in an area, they're not gonna rise from the dead again.

Lower Rate Instead of Zero

Consider Respawn Hours 720 (a month) and Respawn Multiplier 0.1. This means if you leave an area for a month, only 10% of its zombies come back – almost negligible in the short term, but ensures the world isn't completely empty years into survival.

Local Respawn Off, Global Migration On

Keep respawn off but leave Redistribute on a moderate value. This way, cleared towns can eventually get repopulated by zombies migrating from elsewhere on the map. You won't get new zombies, but existing ones might eventually wander into cleared areas.

What to Expect in a No-Respawn World

How does the gameplay change when zombies don't respawn?

Early Game

In the first days and weeks, you won't notice a huge difference except perhaps slightly fewer stragglers behind you. There's still a hefty initial population to contend with. Each kill is a small victory because it's one less to ever deal with again.

Mid Game (Cleared Zones)

After systematically destroying all zombies in an area, that area becomes relatively safe. You might walk down Main Street and find it eerily empty. This can shift the game from constant combat to an eerie post-apocalypse scavenging and base-building vibe. Just be cautious: neighboring areas will still have zombies that can wander in if you make noise.

Late Game (Horde Hunts)

Eventually, you might find yourself actively seeking out remaining pockets of zombies because your immediate surroundings have none. The challenge becomes more about travel and sustainability. It can become a story of reclamation: maybe you clear town after town, doing a "sweep" of the map. Each area cleared is permanently safer, making cross-country trips easier.

Beware Overconfidence!

The biggest threat in a no-respawn game is thinking an area is 100% safe when maybe a few unseen zombies were still around or wandered in. Complacency can still get you killed – all it takes is one surprise shambler in your supposedly secure base to bite you while you're organizing loot.

Multiplayer Dynamics

On a server, disabling respawn creates a very different vibe:

  • The community could work together to clear a town and actually succeed in making a safe settlement
  • Great for RP (roleplay) servers – imagine a safe zone that's genuinely safe because the players cleared it
  • If new players join late, they may have to travel far to find zombies to fight
  • With no respawn, PvE servers will eventually run out of zombies, so sometimes admins schedule soft resets or encourage moving to new regions

Build 42 Specific Issues & Fixes

Build 42 Sandbox Settings Bug

Early B42 builds had a serious glitch: changing zombie spawn settings in sandbox often caused spawn count to max out instead. If you're experiencing excessive zombies after trying to reduce their numbers, this might be why.

By now, Build 42's unstable branch has seen some fixes. Here are some key changes and workarounds:

Wilderness Spawn Changes

The devs removed "wilderness spawns" by default in patch 42.6, meaning forests won't automatically populate with zombies. This was a welcome change as many players reported remote cabins getting swarmed for no apparent reason in earlier B42 versions.

Workaround for Spawn Glitch

If you're on an early B42 build with the spawn settings bug, start with a preset like Apocalypse, then as soon as you load in, use admin powers or the Change Sandbox Options mod to set Respawn to 0. This avoids the glitch where changing settings at world creation makes everything max out.

Useful Mods for Build 42 Spawn Issues

P42 Wilderness Spawn Tweaks

By Plasmasnack - Originally let you disable wilderness spawns; by 42.6 the patch made "none" the default, but the mod still allows customizing if you want some wilderness zombies.

Ducks' Zombie Spawn Fix

Addresses a specific bug where zombies in buildings would pop into existence only when you enter (which can feel like respawn). Forces interior zombies to spawn on chunk load instead of when you open a door.

Build 41 vs Build 42 Zombie Behavior Comparison

Aspect Build 41 Behavior Build 42 Behavior
Respawn Default 10% every 72 hours Same base values but feels more aggressive due to migration
Zombie Migration Exists but less noticeable Much more aggressive, hordes of up to 50 zombies will move to fill cleared areas
Horde Size Rally Group Size: 20 Rally Group Size: 50 (zombies form larger groups)
Wilderness Spawns Moderate in remote areas Initially high in B42, but removed in patch 42.6
Known Bugs Generally stable respawn mechanics Early B42 - changing spawn settings in sandbox could max them out instead
Patch History: Zombie Spawn System Changes
Date (Build) Change Note & Context Impact on Gameplay
Dec 20, 2021
(B41.65)		 "Added Advanced Zombie Options to Sandbox." Introduced granular settings for respawn, unseen hours, etc., in stable build. Players could fine-tune or disable zombie respawn for the first time without mods. Huge for custom difficulty.
Nov 28, 2024
(Thursdoid)		 Dev preview of Build 42's Zombie Heatmap system and combat rework. Zombies no longer static – more organic movement and redistribution. Clearing areas became harder as zombies don't stay put.
Dec 17, 2024
(B42 Unstable)		 Build 42 Unstable released. Noted that "zombie distribution and combat changes" may unbalance game. Multiplayer initially disabled. Zombies concentrated in new ways; players reported extreme spawns in some areas. Marked the start of iterative balancing of respawn/migration.
Jan 4, 2025
(B42.5)		 Spawn Rate Glitch identified. Changing zombie population settings in sandbox caused max population bug. Breaking bug: lower spawn settings actually made more zombies. Community workaround was to avoid sandbox tweaks or use mods until fixed.
Jan 13, 2025
(B42.5.1 Hotfix)		 "Slight fixes to zombie heat map. Some remote locations had too many [zombies]." (Patch notes). Reduced zombie density in wilderness/remote cells. Eased the pressure on starting in rural areas (prior, even farmlands swarmed).
Mar 19, 2025
(B42.6)		 Removed all "wilderness" spawning by default. (Per modder notes). Essentially, Wilderness = None in vanilla now. No more zombies spawning deep in forests over time. Makes truly isolated cabins viable long-term if cleared. Zombies now mostly stick to urban and peripheries unless migrated.
SURVIVOR STORY

I once tried a no-respawn run in West Point – after weeks of bloody work, I actually cleared the entire downtown. It was surreal walking those streets with every shop door wide open, knowing I'd personally "evicted" all the former tenants. It felt great… until a helicopter dragged about two hundred zombies from the outskirts straight into my peaceful town square barbeque.

I learned two things: 1) Always be ready for wandering hordes, even in a no-respawn game, and 2) never grill indoors (half my base burned down in that barbeque 🙃). So, plan accordingly and enjoy the unique challenges of a finite-zombie world!