Crabkingclawbrain

Based on game build 722832 | Last updated: 2026-04-18

Overview

Crabkingclawbrain defines the AI behavior tree for the Crab King's claw entity in Don't Starve Together. This brain coordinates combat actions, boat-circling maneuvers, leash behavior, and wandering patterns. It integrates with the combat component for attack logic and knownlocations for spawn point tracking. The behavior tree uses a priority node structure where higher-priority actions (attacking) take precedence over movement behaviors. Configuration constants such as WAMDER_DIST, TARGET_LEASH_DIST, and CRABKING_RADIUS are defined at the module level (local variables) to tune movement constraints. These are not instance properties and cannot be modified per-entity.

Usage example

local CrabkingClawBrain = require("brains/crabkingclawbrain")
local inst = CreateEntity()
inst:AddComponent("combat")
inst:AddComponent("knownlocations")
inst.crabking = crabking_entity -- reference to parent Crab King

-- Instantiate and run the brain
local brain = CrabkingClawBrain(inst)
RunBrain(inst, brain)

Dependencies & tags

External dependencies:

• behaviours/chaseandattack -- chase and attack behavior node
• behaviours/runaway -- flee behavior node
• behaviours/wander -- wandering behavior node
• behaviours/doaction -- action execution behavior node
• behaviours/attackwall -- wall attack behavior node
• behaviours/panic -- panic behavior node
• behaviours/minperiod -- minimum period behavior node
• behaviours/leash -- leash constraint behavior node
• behaviours/leashandavoid -- leash with avoidance behavior node

Components used:

• combat -- checks InCooldown(), accesses target and attackrange properties
• knownlocations -- calls GetLocation() and RememberLocation() for spawn point tracking
• hull -- calls GetRadius() on platform entities for circle boat calculation

Tags:

• None identified

Properties

Property	Type	Default Value	Description
bt	table	nil	Behavior tree instance created in OnStart()

Main functions

CrabkingClawBrain(inst)

• Description: Constructor that initializes the brain for the given entity instance. Calls parent Brain constructor.
• Parameters: inst -- the entity instance this brain controls
• Returns: Brain instance
• Error states: None

OnStart()

• Description: Initializes the behavior tree root node with priority-ordered behaviors. Sets up attack, circle boat, leash/avoid, and wander nodes in descending priority order.
• Parameters: None
• Returns: None
• Error states: Errors if self.inst.components.combat or self.inst.components.knownlocations are not present on the entity.

OnInitializationComplete()

• Description: Records the entity's current world position as the "spawnpoint" location for wander behavior reference.
• Parameters: None
• Returns: None
• Error states: Errors if self.inst is nil or if self.inst.components.knownlocations is not present on the entity. Errors if self.inst.Transform is nil when calling GetWorldPosition().

findavoidanceobjectfn(inst)

• Description: Returns the Crab King entity reference for avoidance calculations.
• Parameters: inst -- the claw entity instance
• Returns: Crab King entity instance or nil if inst.crabking is not set
• Error states: None

AttackTarget(inst)

• Description: Creates an attack action if combat cooldown is ready, target exists, and target is within attack range. Faces the target before attacking.
• Parameters: inst -- the claw entity instance
• Returns: BufferedAction instance if attack conditions met, nil otherwise
• Error states: Errors if inst.components.combat is nil. Errors if target:GetPosition() returns nil (no guard before inst:FacePoint() call).

CircleBoat(inst)

• Description: Calculates a circular positioning point around the target's boat platform. Used for leash and avoid behavior to maintain distance while circling.
• Parameters: inst -- the claw entity instance
• Returns: Vector3 position for circling, or nil if target or platform not found
• Error states: Errors if inst.components.combat is nil. Errors if platform.components.hull is nil (no guard before GetRadius() call). Errors if target.Transform or platform.Transform is nil (no guard before GetWorldPosition() calls).

Events & listeners

None.