Klaus

Based on game build 714014 | Last updated: 2026-03-05

Overview

klaus.lua defines the prefab and core behavior of Klaus, a boss entity in Don't Starve Together. It coordinates multiple components (health, combat, commander, grouptargeter, sleeper, sanityaura, etc.) to implement a multi-phase boss with phase transitions (based on health thresholds), helper summoning (red and blue deer), music control, chain-breaking mechanics (Unchained state), and rage state activation. The prefab is initialized using a factory function fn() and supports client-server network synchronization via net_bool variables.

Usage example

Klaus is not intended to be manually instantiated by mods. It is instantiated by the game via its prefab definition. However, modders can interact with its public methods on the master server:

-- Example of triggering an action in the game logic (e.g., after an event)
local klaus = TheWorld:FindPrefab("klaus")
if klaus and not klaus.components.health:IsDead() then
    klaus:PushEvent("transition") -- Forces phase transition manually
    klaus:SpawnDeer() -- Manually spawn deer helpers
end

Dependencies & tags

Components used: spawnfader, inspectable, lootdropper, sleeper, locomotor, health, healthtrigger, combat, explosiveresist, grouptargeter, commander, timer, sanityaura, epicscare, knownlocations, drownable, burnable, freezable, talker (via Say call).
Tags added: epic, noepicmusic, monster, hostile, scarytoprey, largecreature, deergemresistance.

Properties

Property	Type	Default Value	Description
engaged	boolean or nil	nil	Indicates whether Klaus is currently engaged in combat (affects health regen and command cooldown).
nohelpers	boolean or nil	nil	Prevents helper summoning until reset (e.g., on entering Phase 2 or rage).
enraged	boolean	false	true when Klaus has entered the enraged state (increased size, scaled stats, no helpers).
recentattackers	table	{}	Maps attacker entities to timer handles (for resetting attacker tracking after 30 seconds).
recentlycharged	table	{}	Maps damaged workable entities to true (to prevent repeated charging damage within 3 seconds).
_unchained	net_bool	false	Networked state indicating whether Klaus's chains have been broken (affects sanity, music, burnable state).
_pausemusic	net_bool	false	Networked state for music pausing (e.g., during boss death or state transitions).
_playingmusic	boolean	false	Local flag to prevent redundant music triggers.
deer_dist	number	3.5	Distance offset for deer positioning relative to Klaus.
hit_recovery	number	TUNING.KLAUS_HIT_RECOVERY	Hit recovery duration (scaled).
attack_range, hit_range	number	TUNING.KLAUS_ATTACK_RANGE, TUNING.KLAUS_HIT_RANGE	Combat ranges (scaled).
chomp_range, chomp_min_range, chomp_hit_range	number	Tuning constants (scaled)	Chomp attack range parameters (scaled).
scrapbook_maxhealth, scrapbook_damage	tables	Arrays of base and enraged values	Exposed for scrapbook display.

Main functions

SetPhysicalScale(inst, scale)

• Description: Adjusts visual scale, shadow size, physics mass, and capsule dimensions for Klaus. Typically used during rage or phase changes.
• Parameters: scale (number) - Multiplicative scale factor.
• Returns: Nothing.
• Error states: No explicit error handling; assumes scale > 0.

SetStatScale(inst, scale)

• Description: Scales Klaus's health, damage, attack period, and ranges using a volume-scaled factor (scale^3). Updates the combat and health components accordingly.
• Parameters: scale (number) - Multiplicative scale factor for stats.
• Returns: Nothing.
• Error states: None.

UpdatePlayerTargets(inst)

• Description: Periodically updates Klaus's target list in grouptargeter by checking which players are within KLAUS_DEAGGRO_DIST of the spawn point location. Adds/withdraws targets dynamically.
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

RetargetFn(inst)

• Description: Called periodically by the combat component to find a new target. Prioritizes players in grouptargeter (especially near spawn) and falls back to random nearby players. Returns a new target and a true flag to continue retargeting.
• Parameters: inst (entity) - Klaus entity.
• Returns: target (entity or nil) and true (to indicate readiness to retarget).
• Error states: May return nil if no valid targets are found.

KeepTargetFn(inst, target)

• Description: Determines if Klaus should continue targeting a player. Returns true only if the target is valid and within KLAUS_DEAGGRO_DIST of the spawn point.
• Parameters:
  • inst (entity) - Klaus entity.
  • target (entity) - Target player.
• Returns: true or false.

SummonHelpers(inst, warning)

• Description: Spawns up to 2 red and 2 blue deer helpers near Klaus based on proximity to recent attackers or current combat target. Sets nohelpers to true to prevent repeat calls. Pushes ms_forcenaughtiness events for penalty calculation.
• Parameters:
  • inst (entity) - Klaus entity.
  • warning (boolean) - Whether to warn nearby players via talker component.
• Returns: true if helpers were spawned; false otherwise.

EnterPhase2Trigger(inst)

• Description: Called when Klaus's health drops to 50% of max. Pushes a "transition" event to trigger animation/state changes for Phase 2 (chain break, enraged).
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

SetEngaged(inst, engaged)

• Description: Manages combat state transition. When engaged=true: stops health regen, sets command cooldown timer, disables newcombattarget callback. When engaged=false: starts regen, resets cooldown, re-enables callback. Resets nohelpers on recovery.
• Parameters:
  • inst (entity) - Klaus entity.
  • engaged (boolean) - Combat engagement state.
• Returns: Nothing.

SpawnDeer(inst)

• Description: Instantiates a red deer and a blue deer, positions them in a spread arc around Klaus, and registers them as soldiers under the commander component.
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

Unchain(inst, warning)

• Description: Breaks Klaus's chains. Unhides chain visuals, enables chain-breaking effects, sets large sanity aura, allows burning (via nocharring=false), disables foley sounds, and sets urchained=true.
• Parameters:
  • inst (entity) - Klaus entity.
  • warning (boolean) - Whether to warn nearby players.
• Returns: Nothing.

Enrage(inst, warning)

• Description: Activates Klaus's rage state: stops physics, teleports to position, scales up size and stats, disables helper spawning, sets large sanity aura, resets combat FX override.
• Parameters:
  • inst (entity) - Klaus entity.
  • warning (boolean) - Whether to warn nearby players.
• Returns: Nothing.

PushMusic(inst, level)

• Description: Triggers the triggeredevent event for the player if within range, to control music volume levels (1=normal, 2=pause, 3=unchained/rage).
• Parameters:
  • inst (entity) - Klaus entity.
  • level (number) - Music level indicator.
• Returns: Nothing.

OnMusicDirty(inst)

• Description: Recalculates music level based on urchained and pausemusic flags and starts/stops a periodic task to update music state.
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

PauseMusic(inst, paused)

• Description: Toggles music pausing by updating _pausemusic net_bool and calling OnMusicDirty.
• Parameters:
  • inst (entity) - Klaus entity.
  • paused (boolean) - true to pause, false to resume.
• Returns: Nothing.

IsUnchained(inst)

• Description: Returns the current urchained state.
• Parameters: inst (entity) - Klaus entity.
• Returns: true if unchained; false otherwise.

FindChompTarget(inst)

• Description: Finds a valid chomp target from AllPlayers: prefers distant targets first, then nearby targets, and falls back to current combat target.
• Parameters: inst (entity) - Klaus entity.
• Returns: target (entity or nil).

OnSave(inst, data)

• Description: Saves nohelpers, unchained, and enraged state into data for world persistence.
• Parameters:
  • inst (entity) - Klaus entity.
  • data (table) - Save data table.
• Returns: Nothing.

OnPreLoad(inst, data)

• Description: Restores saved state (nohelpers, unchained, enraged) after loading from a save file.
• Parameters:
  • inst (entity) - Klaus entity.
  • data (table or nil) - Loaded save data.
• Returns: Nothing.

OnEntitySleep(inst)

• Description: Starts a 10-second delayed removal task for Klaus (and his deer) when world enters sleep mode, unless Klaus is unchained and dead.
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

OnEntityWake(inst)

• Description: Cancels the sleep removal task if Klaus wakes up.
• Parameters: inst (entity) - Klaus entity.
• Returns: Nothing.

OnAttacked(inst, data)

• Description: Handles damage event: adds attacker to recentattackers, updates combat target if needed, and shares attacker to all soldiers.
• Parameters:
  • inst (entity) - Klaus entity.
  • data (table) - Attack event data.
• Returns: Nothing.

OnCollide(inst, other)

• Description: On physics collision with a workable entity, schedules OnDestroyOther (with 2-FRAME delay) to destroy the workable and prevent rapid recharging.
• Parameters:
  • inst (entity) - Klaus entity.
  • other (entity) - Collided entity.
• Returns: Nothing.

OnDestroyOther(inst, other)

• Description: Destroys a workable entity (except dig/net) by triggering its destroy action. Prevents repeated charging with recentlycharged cooldown.
• Parameters:
  • inst (entity) - Klaus entity.
  • other (entity) - Workable entity to destroy.
• Returns: Nothing.

Events & listeners

• Listens to:
  • attacked - Calls OnAttacked.
  • musicdirty (client) - Calls OnMusicDirty.
  • newcombattarget - Calls OnNewTarget (only when not engaged).
• Pushes:
  • "transition" - On health dropping to 50%.
  • "soldierschanged" (via commander) - Soldier list changes.
  • "ms_forcenaughtiness" (via TheWorld:PushEvent) - For Naughty player scoring.
  • "triggeredevent" (via ThePlayer:PushEvent) - For music control.