Project Zomboid Zombie Settings for Your Server: Speed, Count and Infection

Where to change them

In the server's <name>_SandboxVars.lua file (servertest_SandboxVars.lua if nobody renamed it), with the server stopped: the ones about what zombies are like are in the ZombieLore block, the ones about how many there are in ZombieConfig, and “Zombie Count”, “Zombie Distribution” and “Zombie Respawn” sit on their own near the top. Watch the numbers: in almost all of them, 1 is the hardest.

If you don't want to edit the file by hand, paste it into the Project Zomboid settings editor: every option shows up with a readable name, you pick and it gives you the file back ready. The rest of the sandbox (loot, power, water) is covered in the sandbox settings guide.

They apply when the server starts again, but not all in the same way: what's generated at the start (how many zombies there are on day one, the map) only fully changes in a new world. If you're going to change a lot, better do it before you start or with a new world.

Whether they sprint: speed

“Speed” (ZombieLore.Speed): 1 “Sprinters”, 2 “Fast Shamblers”, 3 “Shamblers” and 4 “Random”. In Build 42 it defaults to “Random”. For none of them to run, 2 or 3; for an action-movie game, 1.

“Random Sprinter Amount” (ZombieLore.SprinterPercentage, from 0 to 100): it only counts with speed on “Random”, and sets what share of them are sprinters. It defaults to 0. With 5 or 10, most walk but every now and then one comes running, which is the scariest thing without making the game impossible.

“Day/Night Zombie Speed Effect” (ZombieLore.ActiveOnly): 1 “Both” (default), 2 “Night” or 3 “Day”. Active zombies move at the chosen speed; inactive ones are slower and tend not to give chase. With sprinters and “Night”, you can go out by day and have to be at the base at night.

How many there are

“Zombie Count” (Zombies): 1 “Insane”, 2 “Very High”, 3 “High”, 4 “Normal” (default), 5 “Low” and 6 “None”. The opposite of what you'd expect: the higher the number, the fewer zombies.

That option is a shortcut for the “Population Multiplier” (ZombieConfig.PopulationMultiplier), which is the real number: Insane 2.5; Very High 1.6; High 1.2; Normal 0.65; Low 0.15 and None 0 (it accepts 0 to 4, so 0.4 also works for something between Low and Normal). If you edit the file by hand, change both so they say the same thing.

The population isn't fixed: it starts with the “Population Start Multiplier” (1.0 by default), grows up to the “Population Peak Multiplier” (1.5) and reaches that peak on the “Population Peak Day” (day 28). If you want a few quiet first days that then get harder, lower the start one and leave the peak; if you don't want it to get worse, set the peak equal to the start.

“Zombie Distribution” (Distribution): 1 “Urban Focused” (default, lots in towns and few in the countryside) or 2 “Uniform”. With “Uniform”, a cabin in the woods is no longer a safe spot.

More zombies means more work for the server: if the game stutters on “High” or “Very High”, it's the first thing worth lowering (the lag guide).

Whether they come back: respawn and migration

“Zombie Respawn” (ZombieRespawn): 1 “High”, 2 “Normal”, 3 “Low” and 4 “None”. In Build 42 it defaults to “None”: what you clear stays clear. Under the hood it's set by “Respawn Hours” (ZombieConfig.RespawnHours, 0 by default = no respawn), “Respawn Unseen Hours” (RespawnUnseenHours) and “Respawn Multiplier” (RespawnMultiplier, what share of the population comes back each time).

“Zombie Migration” (ZombieMigrate, on by default): zombies gradually move towards empty areas, even if they don't respawn. A cleared street doesn't stay empty forever.

Infection: whether a bite turns you

“Transmission” (ZombieLore.Transmission): 1 “Blood and Saliva” (default: bites, and also scratches and lacerations, can infect), 2 “Saliva Only” (only bites), 3 “Everyone's Infected” (when you die, you rise as a zombie even if nobody bit you) and 4 “None” (nobody gets infected). For a building game without the fear of losing your character to a bite, “None”.

“Infection Mortality” (ZombieLore.Mortality): how long the infection takes to kill you, from 1 “Instant” to 6 “1-2 Weeks” and 7 “Never”. By default, 5 “2-3 Days”.

“Reanimate Time” (ZombieLore.Reanimate): how long an infected corpse takes to rise, from “Instant” to “1-2 Weeks”. By default, 3 “0-1 Minutes”: if a friend dies infected, don't hang around next to them. What happens to their character and their stuff is in dying on a Zomboid server.

How smart they are: doors, memory, sight and hearing

“Cognition” (ZombieLore.Cognition): 1 “Navigate and Use Doors”, 2 “Navigate”, 3 “Basic Navigation” (default) and 4 “Random”. With 1, closing the door is no longer enough. There's also “Random Door Opening Amount” (DoorOpeningPercentage, from 0 to 100, 0 by default).

“Memory” (ZombieLore.Memory): how long they remember you after seeing or hearing you, from 1 “Long” to 4 “None”, with 5 and 6 random. By default, “Normal”. With “Long”, shaking them off is much harder.

“Sight” (ZombieLore.Sight) and “Hearing” (ZombieLore.Hearing): from 1 “Eagle” or “Pinpoint” to 3 “Poor”, with 4 “Random” and 5 “Random between Normal and Poor”, which is the default for both. Setting them to “Normal” makes the game a lot tenser without touching the count.

“New Stealth System” (ZombieLore.SpottedLogic, on by default): hiding behind cars counts, and so do your traits and the weather.

How tough they are, and your base

“Strength” (ZombieLore.Strength): the damage each zombie does when it attacks, from 1 “Superhuman” to 3 “Weak”, and 4 “Random”. By default, “Normal”.

“Toughness” (ZombieLore.Toughness): how hard they are to kill, 1 “Tough”, 2 “Normal”, 3 “Fragile” or 4 “Random” (default). With “Fragile”, a game with lots of zombies is easier to handle.

“Drag Down” (ZombieLore.ZombiesDragDown, on by default): if several attack you at once they can pull you to the ground and kill you, depending on their strength. It's what causes the most “unfair” deaths for beginners.

“Damage Construction” (ZombieLore.ThumpOnConstruction, on by default): whether they can break your fences, walls and barricades. “Environmental Attacks” (ThumpNoChasing) makes them hit doors and constructions even if they haven't seen you. If you're into building, turning off the first one gives a lot of peace of mind; and if not, “Zombies To Damage Fences” and “Fence Damage Multiplier” set how many it takes and how fast.

Four combinations that work

These are our advice, not the game's; each one starts from the Build 42 defaults and only changes what's mentioned.

To build in peace: “Zombie Count” on “Low” (multiplier 0.15), “Toughness” on “Fragile”, “Transmission” on “None” and “Damage Construction” off.

The classic, scary but not overwhelming: speed “Random” with 5% sprinters, “Sight” and “Hearing” on “Normal” and everything else at default.

Night sprinters: speed “Sprinters” and “Day/Night Zombie Speed Effect” on “Night”. By day you go out scavenging; when night falls, everyone back to base.

For veterans: “Zombie Count” on “High”, speed “Random” with 20% sprinters, “Cognition” with doors, “Memory” “Long” and respawn “Normal”. Before that, make sure everyone knows what happens when you die.

If you're starting the game as a group, which mode and settings to choose puts it together with power, water and XP.

On NapNodes

The panel's “Settings” has all these settings, in “Zombie lore”, “How many zombies and where” and “World: zombies”, with a search box: type “zombie”, “speed” or “transmission”. They save automatically and apply when you press “Restart”. Before a big change, make a backup in “Backups”.

A Zomboid server on NapNodes has at least 6 GB of RAM, all yours, and if you raise the zombie count a lot or add many mods, the RAM guide tells you when you need more. To try out combinations before paying anything, there's the free Project Zomboid server.

Frequently asked questions