WX-78 Possessed Body Brain

Based on game build 722832 | Last updated: 2026-04-28

Overview

Wx78_PossessedBodyBrain is the AI behavior tree for WX-78's possessed body prefab. It currently implements only a StandStill behavior node, causing the entity to remain stationary. Brains are paused automatically when the entity is far from players and resume on player proximity. The behavior tree is attached via inst:SetBrain(Wx78_PossessedBodyBrain).

Usage example

-- Brains are attached during prefab construction:
local brain = require("brains/wx78_possessedbodybrain_no_package")
inst:SetBrain(brain)

-- The framework calls OnStart() to obtain the behaviour tree.
-- Manual access to the running tree:
if inst.brain ~= nil and inst.brain.bt ~= nil then
    -- inspect or reset the running behaviour tree
end

Dependencies & tags

External dependencies:

• behaviours/wander -- Wander behavior node factory (imported but not used in current implementation)
• behaviours/faceentity -- FaceEntity behavior node factory (imported but not used in current implementation)
• behaviours/chaseandattack -- ChaseAndAttack behavior node factory (imported but not used in current implementation)
• behaviours/doaction -- DoAction behavior node factory (imported but not used in current implementation)
• behaviours/leash -- Leash behavior node factory (imported but not used in current implementation)
• behaviours/standstill -- StandStill behavior node factory (actively used)
• brains/braincommon -- imported but not referenced (unused import)

Components used: None identified — behavior nodes access components internally; this brain file does not directly access inst.components.X.

Tags: None identified

Properties

Property	Type	Default Value	Description
UPDATE_RATE	constant (local)	0.5	Behavior tree update interval in seconds. Passed to PriorityNode to control how often the tree evaluates behavior conditions.

Main functions

OnStart()

• Description: Constructs the root PriorityNode of the behavior tree containing only a StandStill behavior. Assigns the resulting BehaviorTree to self.bt. Called once when the brain is attached and on resume after pause.
• Parameters: self -- the brain instance (implicit via method syntax)
• Returns: None (assigns self.bt internally)
• Error states: None

OnStop()

• Description: Cleanup callback when the brain is stopped or detached. Currently empty — no cleanup logic required for this brain.
• Parameters: self -- the brain instance (implicit via method syntax)
• Returns: None
• Error states: None

Events & listeners

None — brain trees react to component state through behavior nodes, not engine events directly. Event handling is done in the brain's host stategraph or via component subscriptions.