# How to Configure Zombie Settings on Your Project Zomboid Server (/docs/project-zomboid/zombie-settings) Zombie behavior is controlled through the `SandboxVars.lua` file. Settings are divided into two groups: `ZombieLore` (individual zombie behavior) and `ZombieConfig` (population and respawning). Editing Zombie Settings [#editing-zombie-settings] On XGamingServer, go to **Files** and open: ``` Zomboid/Server/[servername]_SandboxVars.lua ``` Zombie lore settings use the `ZombieLore` prefix: ```lua title="SandboxVars.lua" SandboxVars = { ZombieLore = { Speed = 2, Strength = 2, Toughness = 2, Transmission = 1, Mortality = 5, Reanimate = 3, }, } ``` Zombie Speed [#zombie-speed] | Value | Setting | Description | | ----- | -------------- | --------------------------------------- | | 1 | Sprinters | Full-speed running zombies (hardest) | | 2 | Fast Shamblers | Brisk walking pace (default Apocalypse) | | 3 | Shamblers | Classic slow zombies | | 4 | Random | Each zombie gets a random speed | Zombie Strength [#zombie-strength] | Value | Setting | Description | | ----- | ---------- | -------------------------------- | | 1 | Superhuman | Very high damage per hit | | 2 | Normal | Default damage | | 3 | Weak | Reduced damage | | 4 | Random | Each zombie gets random strength | Zombie Toughness [#zombie-toughness] | Value | Setting | Description | | ----- | ------- | --------------------------------- | | 1 | Tough | Takes more hits to kill | | 2 | Normal | Default health | | 3 | Fragile | Dies easily | | 4 | Random | Each zombie gets random toughness | Zombie Cognition [#zombie-cognition] | Value | Setting | Description | | ----- | -------------------- | --------------------------------------------------- | | 1 | Navigate + Use Doors | Smartest — can open doors and path around obstacles | | 2 | Navigate | Can path around obstacles but cannot open doors | | 3 | Basic Navigation | Minimal intelligence (default) | | 4 | Random | Each zombie gets random cognition | Day/Night Activity [#daynight-activity] Controls when zombies are most active. Combine with Speed settings for interesting gameplay. | Value | Setting | Description | | ----- | ------- | ----------------------------------------- | | 1 | Both | Active day and night equally (default) | | 2 | Night | More active at night, sluggish during day | | 3 | Day | More active during day, sluggish at night | > 💡 **Tip:** Set `ActiveOnly = 2` with `Speed = 1` to create **night sprinters** — zombies that sprint at night but are slow during the day. This is one of the most popular custom configurations. Zombie Senses [#zombie-senses] Sight [#sight] | Value | Setting | | ----- | ----------------------- | | 1 | Eagle (very long range) | | 2 | Normal (default) | | 3 | Poor (short range) | | 4 | Random | Hearing [#hearing] | Value | Setting | | ----- | ----------------------------- | | 1 | Pinpoint (extremely accurate) | | 2 | Normal (default) | | 3 | Poor | | 4 | Random | Smell [#smell] | Value | Setting | | ----- | ----------------------------- | | 1 | Bloodhound (strong detection) | | 2 | Normal (default) | | 3 | Poor | Memory [#memory] | Value | Setting | | ----- | ------------------------------------------ | | 1 | Long (remembers your position a long time) | | 2 | Normal (default) | | 3 | Short | | 4 | None (forgets immediately) | | 5 | Random | Decomposition [#decomposition] Controls how zombies change over months of game time. | Value | Setting | Description | | ----- | ----------------- | --------------------------------------- | | 1 | Slows and Weakens | Zombies get slower AND weaker over time | | 2 | Slows | Zombies slow down but maintain strength | | 3 | Weakens | Zombies weaken but maintain speed | | 4 | No Effect | Zombies never decompose (default) | Zombie Behavior Flags [#zombie-behavior-flags] | Setting | Type | Default | Description | | --------------------- | ------- | ------- | -------------------------------------------------------- | | `ThumpNoChasing` | boolean | false | Zombies attack structures even when not chasing a player | | `ThumpOnConstruction` | boolean | true | Zombies destroy player-built constructions | | `TriggerHouseAlarm` | boolean | false | Zombies can trigger house alarms | | `ZombiesDragDown` | boolean | true | Zombies can drag players to the ground | | `ZombiesFenceLunge` | boolean | true | Zombies can lunge over fences | Fake Dead (Playing Possum) [#fake-dead-playing-possum] | Value | Setting | | ----- | -------------------------------------------------------------- | | 1 | Some zombies pretend to be dead — reanimate when you get close | | 2 | Even killed zombies may get back up | | 3 | Never pretend dead (all corpses are truly dead) | Crawl Under Vehicles [#crawl-under-vehicles] | Value | Setting | | ----- | --------------- | | 1 | Crawlers Only | | 2 | Extremely Rare | | 3 | Rare | | 4 | Sometimes | | 5 | Often (default) | | 6 | Very Often | | 7 | Always | Population Settings [#population-settings] These use the `ZombieConfig` prefix: | Setting | Default | Description | | --------------------------- | ------- | -------------------------------------------------------------- | | `PopulationMultiplier` | 1.0 | Overall zombie population (0.0 = none, 4.0 = insane) | | `PopulationStartMultiplier` | 1.0 | Population multiplier on day 1 | | `PopulationPeakMultiplier` | 1.0 | Population multiplier at peak day | | `PopulationPeakDay` | 28 | Day when population reaches its peak | | `RespawnHours` | 72.0 | Hours before zombies respawn in cleared areas (0 = no respawn) | | `RespawnUnseenHours` | 16.0 | Hours a cell must be unseen before respawn | | `RespawnMultiplier` | 0.1 | Fraction of original zombies that respawn each cycle | | `RedistributeHours` | 12.0 | How often zombies migrate across the map | | `FollowSoundDistance` | 100 | Distance (tiles) zombies will investigate sounds | | `RallyGroupSize` | 20 | Maximum zombie group/horde size | | `RallyTravelDistance` | 20 | Distance groups will migrate | | `RallyGroupSeparation` | 15 | Minimum distance between groups | | `RallyGroupRadius` | 3 | Radius of a zombie group | Population Scale [#population-scale] | `PopulationMultiplier` | Label | | ---------------------- | --------- | | 0.0 | None | | 0.35 | Low | | 1.0 | Normal | | 2.0 | High | | 3.0 | Very High | | 4.0 | Insane | Infection and Mortality [#infection-and-mortality] Infection settings are also under `ZombieLore`. See [Infection and Mortality](/docs/project-zomboid/infection-settings) for the full guide covering transmission, mortality timelines, and reanimation. Recommended Presets [#recommended-presets] Casual PvE [#casual-pve] ```lua title="SandboxVars.lua" ZombieLore = { Speed = 3, Strength = 3, Toughness = 3, Transmission = 4, Cognition = 3, Memory = 3, Sight = 3, Hearing = 3, ActiveOnly = 1, Decomp = 1, DisableFakeDead = 3, }, ZombieConfig = { PopulationMultiplier = 0.5, RespawnHours = 0.0, }, ``` Slow, weak zombies with no infection and no respawning. Night Sprinters [#night-sprinters] ```lua title="SandboxVars.lua" ZombieLore = { Speed = 1, Strength = 2, Toughness = 2, ActiveOnly = 2, Sight = 1, Hearing = 1, Memory = 1, DisableFakeDead = 1, }, ZombieConfig = { PopulationMultiplier = 1.5, }, ``` Sprinting zombies at night, sluggish during the day. Eagle eyesight and pinpoint hearing. Hardcore Survival [#hardcore-survival] ```lua title="SandboxVars.lua" ZombieLore = { Speed = 1, Strength = 1, Toughness = 1, Transmission = 1, Mortality = 5, Cognition = 1, Sight = 1, Hearing = 1, Memory = 1, ZombiesDragDown = true, ZombiesFenceLunge = true, Decomp = 4, }, ZombieConfig = { PopulationMultiplier = 4.0, PopulationPeakDay = 14, }, ``` Maximum population sprinters that can open doors. No decomposition. Peak at day 14. No Zombies (Building Server) [#no-zombies-building-server] ```lua title="SandboxVars.lua" ZombieConfig = { PopulationMultiplier = 0.0, RespawnHours = 0.0, }, ``` Related Guides [#related-guides] See also: [Infection and Mortality](/docs/project-zomboid/infection-settings) | [Sandbox Settings](/docs/project-zomboid/sandbox-settings) | [Loot Respawn](/docs/project-zomboid/loot-respawn) | [Configure Your Server](/docs/project-zomboid/server-config) If you need help, join our [Discord](https://discord.xgamingserver.com/).