API Reference

Documentation Unreal Engine AI Reference

Controller-side C++ and Blueprint API: SECCombatControllerComponent, EnemyControllerBase, SECBrainComponent, and BotStateTreeAIComponent.


The controller-side classes and their public members. For building an enemy, start with Getting Started; this page is the reference you reach for when extending the system in Blueprint or C++.

SECCombatControllerComponent

The hub every setup needs. Add it to any AAIController and the combat system works. It resolves the AI config, registers combat roles, syncs role-based state, and orchestrates death.
To read the config or role from outside the component, call the static helpers instead of casting to AEnemyControllerBase. They work on any controller carrying the component.
Static helpers
FunctionReturns
ResolveAIConfig(Controller)The controller's cached config, or the pawn's config via IEnemyAIConfigProvider, or null
ResolveCurrentCombatRole(Controller)The current combat role tag, or an empty tag
Instance accessors
FunctionReturns
GetCachedAIConfig()The resolved UEnemyAIConfig in use
GetCurrentCombatRole()The current combat role tag
Overridable hooks (BlueprintNativeEvent, call the parent to keep default behavior)
FunctionPurpose
SyncStateForCombatRole(RoleTag)Runs when the role changes. Override to swap animation sets, trigger effects, or switch StateTree assets. Call Super to keep the default action set and movement profile sync.
HandleCombatTargetLost(LostTarget)Runs when the target is destroyed or unregistered. Override for fallback behavior (patrol, switch aggro). The default broadcasts OnCombatTargetLost.
Blueprint-callable
FunctionPurpose
ApplyLocalCombatRole(RoleTag)Adopt a role locally without registering with the subsystem. Syncs the action set and movement profile like a subsystem-assigned role, but consumes no slots and joins no coordination. For bosses and solo enemies.
HandleDeath()Full SEC shutdown, idempotent. Stops the brain, cancels the in-flight action and reaction, stops melee tracing, disables threat detection, unregisters from the role subsystem, clears focus, then broadcasts OnDeath. Does not unpossess or destroy the pawn.
Properties
PropertyDefaultPurpose
DefaultAIConfignullFallback config when the pawn provides none via IEnemyAIConfigProvider
bAutoRegisterForCombatRolestrueRegister with the combat role subsystem on possession
RoleRegistrationParamsn/aRegistration parameters used when the pawn has no config
bEnableThreatDetectiontrueEnable threat detection on BeginPlay when a ThreatDetectionComponent is present
bAutoBindBasicHealthComponenttrueCall HandleDeath() automatically when a BasicHealthComponent reaches zero
bDropWeaponOnDeathtrueDrop the weapon with a 10-second physics lifespan on death
Delegates
DelegateFires
OnCombatRoleChanged(NewRole, OldRole)When the role changes, from subsystem assignment or local apply
OnCombatTargetLost(LostTarget)When the target is destroyed or unregistered
OnCombatRoleSystemReady(Controller)After registration with the role subsystem. Safe to read the initial role here
OnDeath()At the end of HandleDeath(), once every system is stopped. Safe to ragdoll, spawn VFX, or destroy

EnemyControllerBase

The convenience controller. It creates every combat component as a default subobject and adds facing and rotation behavior on top of SECCombatControllerComponent.
Rotation lock (freezes facing during a committed attack)
FunctionPurpose
LockRotationBy(LockOwner)Hold a rotation lock keyed to an owner. Releases when the owner is destroyed, or when an InstancedPerActor ability goes inactive. Defaults to the caller.
UnlockRotationBy(LockOwner)Release that owner's lock
LockRotation() / UnlockRotation()Keyless counter-based lock; balance each call
ForceUnlockRotation()Clear both the counter and the owner set
IsRotationLocked()True while any lock holds
UGameplayAbilityBase locks rotation through this API when bLockAIRotation is set, so montage-driven attacks commit without extra wiring.
Facing
MemberDefaultPurpose
GetDesiredFacingLocation(OutLocation)n/aBlueprintNativeEvent returning the world location to face. Override for custom facing
SmoothFocusInterpSpeed165.0Interpolation speed for smooth focus rotation
bFaceLastKnownWhenNotDetectedtrueTrack the live target only while Detected; otherwise face its last-known location instead of through walls
Team
MemberPurpose
TeamIdEditable per instance. 0 = player, 1 = enemy (default), 255 = neutral
ISECTeamInterfaceGetSECTeamId / SetSECTeamId
IGenericTeamAgentInterfaceIntegrates with AI Perception and EQS
Blueprint events (forwarded from the combat component)
EventFires
K2_OnCombatRoleAssigned(NewRole, OldRole)On role assignment
K2_OnCombatTargetLost(LostTarget)When the target is lost
K2_OnReactionSetApplied(RoleTag, ReactionSet)When a reaction set is applied via role sync
K2_OnDeath()After HandleDeath() completes; safe to ragdoll or play a death montage
HandleDeath() on the controller is a convenience wrapper around the component's HandleDeath(). Component accessors: GetCombatControllerComponent, GetHelperBTComponent, GetReactionEvaluationComponent, GetAwarenessComponent. Delegates: OnFocusSet, OnActionStateChanged.

SECBrainComponent

Chooses how the AI runs from its config: a StateTree when one is named, otherwise a native C++ combat loop.
MemberDefaultPurpose
RefreshBrain()n/aRe-evaluate the config and switch brains if the StateTree choice changed. Call after changing the config at runtime without re-possessing
IsRunningNativeBrain()n/aTrue while the native loop drives the AI
EvaluationCooldown0.1Seconds between action evaluations in the native loop
In native mode the component holds the controller's brain slot, so HandleDeath stops it and the per-action behavior-tree swap restores it.

BotStateTreeAIComponent

Extends Unreal's UStateTreeAIComponent. SECBrainComponent creates it at runtime when the config names a StateTree. It resolves the config on possession in this order:
  1. The controller's SECCombatControllerComponent cached config
  2. A pawn implementing IEnemyAIConfigProvider
  3. The FallbackStateTree on this component
MemberDefaultPurpose
InitializeFromAIConfig(AIConfig)n/aLoad and set the StateTree from the config's DefaultStateTree. Returns true on success
AddLinkedStateTreeOverride(StateTag, StateTreeReference)n/aSwap a sub-tree per gameplay tag, for enemy variants
bAutoInitializeFromConfigtrueInitialize from the config automatically on possession. Disable for manual control
FallbackStateTreenullUsed when no config is found or the config names no StateTree