diff --git a/modules/wave_survival/enemy_body.cpp b/modules/wave_survival/enemy_body.cpp
index d8bccc89..8d9d92ba 100644
--- a/modules/wave_survival/enemy_body.cpp
+++ b/modules/wave_survival/enemy_body.cpp
@@ -6,6 +6,15 @@ void EnemyBody::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("set_movement_direction", "direction"), &self_type::set_movement_direction);
 }
 
+void EnemyBody::on_child_added(Node *node) {
+	if (StateMachine *fsm{ cast_to<StateMachine>(node) }) {
+		this->fsm = fsm;
+	}
+	if (NavigationAgent3D *nav{ cast_to<NavigationAgent3D>(node) }) {
+		this->nav = nav;
+	}
+}
+
 void EnemyBody::ready() {
 	this->fsm = cast_to<StateMachine>(get_node(NodePath("%StateMachine")));
 	this->nav = cast_to<NavigationAgent3D>(get_node(NodePath("%NavigationAgent3D")));
@@ -50,6 +59,10 @@ NpcUnit *EnemyBody::get_unit() const {
 	return this->unit;
 }
 
+HealthStatus *EnemyBody::get_health() const {
+	return this->health;
+}
+
 NavigationAgent3D *EnemyBody::get_nav() const {
 	return this->nav;
 }
diff --git a/modules/wave_survival/enemy_body.h b/modules/wave_survival/enemy_body.h
index 3949c109..2ff1016c 100644
--- a/modules/wave_survival/enemy_body.h
+++ b/modules/wave_survival/enemy_body.h
@@ -10,6 +10,7 @@ class NpcUnit;
 class EnemyBody : public CharacterBody3D {
 	GDCLASS(EnemyBody, CharacterBody3D);
 	static void _bind_methods();
+	void on_child_added(Node *node);
 	void ready();
 	void physics_process(double delta);
 
@@ -20,6 +21,7 @@ public:
 	void set_unit(NpcUnit *unit);
 	NpcUnit *get_unit() const;
 
+	HealthStatus *get_health() const;
 	NavigationAgent3D *get_nav() const;
 	void set_movement_speed(float value);
 	float get_movement_speed() const;
@@ -33,6 +35,7 @@ private:
 
 	StateMachine *fsm{ nullptr };
 	NpcUnit *unit{ nullptr };
+	HealthStatus *health{ nullptr };
 	NavigationAgent3D *nav{ nullptr };
 	Vector2 unit_offset{ 0, 0 };
 };
diff --git a/modules/wave_survival/map_region.cpp b/modules/wave_survival/map_region.cpp
index e266b2f9..ab1c9552 100644
--- a/modules/wave_survival/map_region.cpp
+++ b/modules/wave_survival/map_region.cpp
@@ -1,7 +1,45 @@
 #include "map_region.h"
+#include "enemy_body.h"
 
 String const MapRegion::sig_phase_changed{ "phase_changed" };
 
 void MapRegion::_bind_methods() {
 	ADD_SIGNAL(MethodInfo(sig_phase_changed, PropertyInfo(Variant::BOOL, "hunt_phase")));
 }
+
+void MapRegion::on_node_entered(Node *node) {
+	if (EnemyBody * body{ cast_to<EnemyBody>(node) }) {
+		if (!this->units.has(body->get_unit())) {
+			body->get_unit()->set_region(this);
+		}
+	}
+}
+
+void MapRegion::ready() {
+	connect("body_entered", callable_mp(this, &self_type::on_node_entered));
+}
+
+void MapRegion::_notification(int what) {
+	if (Engine::get_singleton()->is_editor_hint()) {
+		return;
+	}
+	switch (what) {
+		default:
+			return;
+		case NOTIFICATION_READY:
+			ready();
+			return;
+	}
+}
+
+void MapRegion::register_unit(NpcUnit *unit) {
+	if (!this->units.has(unit)) {
+		this->units.insert(unit);
+	}
+}
+
+void MapRegion::remove_unit(NpcUnit *unit) {
+	if (this->units.has(unit)) {
+		this->units.erase(unit);
+	}
+}
diff --git a/modules/wave_survival/map_region.h b/modules/wave_survival/map_region.h
index 01ff6cf2..663e55ea 100644
--- a/modules/wave_survival/map_region.h
+++ b/modules/wave_survival/map_region.h
@@ -1,15 +1,27 @@
 #ifndef MAP_REGION_H
 #define MAP_REGION_H
 
+#include "core/templates/hash_set.h"
+#include "npc_unit.h"
 #include "scene/3d/physics/area_3d.h"
 
 class MapRegion : public Area3D {
 	GDCLASS(MapRegion, Area3D);
 	static void _bind_methods();
+	void on_node_entered(Node *node);
+	void ready();
+
+protected:
+	void _notification(int what);
+
+public:
+	void register_unit(NpcUnit *unit);
+	void remove_unit(NpcUnit *unit);
 
 private:
 	float awareness{ 0.f };
 	bool hunt_phase{ false };
+	HashSet<NpcUnit *> units{ nullptr };
 
 public:
 	static String const sig_phase_changed;
diff --git a/modules/wave_survival/npc_unit.cpp b/modules/wave_survival/npc_unit.cpp
index 7111be73..9df31166 100644
--- a/modules/wave_survival/npc_unit.cpp
+++ b/modules/wave_survival/npc_unit.cpp
@@ -1,6 +1,7 @@
 #include "npc_unit.h"
 #include "enemy_body.h"
 #include "macros.h"
+#include "map_region.h"
 #include "patrol_path.h"
 #include "player_detector.h"
 
@@ -63,3 +64,18 @@ void NpcUnit::set_patrol_speed(float speed) {
 float NpcUnit::get_patrol_speed() const {
 	return this->patrol_speed;
 }
+
+void NpcUnit::set_region(MapRegion *region) {
+	if (this->region == region) {
+		return;
+	}
+	if (this->region != nullptr) {
+		this->region->remove_unit(this);
+	}
+	this->region = region;
+	region->register_unit(this);
+}
+
+MapRegion *NpcUnit::get_region() const {
+	return this->region;
+}
diff --git a/modules/wave_survival/npc_unit.h b/modules/wave_survival/npc_unit.h
index 6f649912..79d6db23 100644
--- a/modules/wave_survival/npc_unit.h
+++ b/modules/wave_survival/npc_unit.h
@@ -5,6 +5,7 @@
 class StateMachine;
 class EnemyBody;
 class PatrolPath;
+class MapRegion;
 
 class NpcUnit : public Node3D {
 	GDCLASS(NpcUnit, Node3D);
@@ -22,12 +23,15 @@ public:
 	bool is_aware_of_player() const; //!< becomes true when any individual in the unit sees the player.
 	void set_patrol_speed(float value);
 	float get_patrol_speed() const;
+	void set_region(MapRegion *region);
+	MapRegion *get_region() const;
 
 private:
 	bool aware_of_player{ false };
 	Vector<EnemyBody *> npcs{};
 	PatrolPath *patrol_path{ nullptr };
 	float patrol_speed{ 1.f };
+	MapRegion *region{ nullptr };
 };
 
 #endif // !NPC_UNIT_H
diff --git a/modules/wave_survival/register_types.cpp b/modules/wave_survival/register_types.cpp
index 36c120c9..41a6231c 100644
--- a/modules/wave_survival/register_types.cpp
+++ b/modules/wave_survival/register_types.cpp
@@ -9,6 +9,7 @@
 #include "wave_survival/hitbox.h"
 #include "wave_survival/hitscan_muzzle.h"
 #include "wave_survival/interactable.h"
+#include "wave_survival/map_region.h"
 #include "wave_survival/muzzle_effect.h"
 #include "wave_survival/npc_unit.h"
 #include "wave_survival/patrol_path.h"
@@ -22,7 +23,6 @@
 #include "wave_survival/state.h"
 #include "wave_survival/state_machine.h"
 #include "wave_survival/weapon_base.h"
-#include "wave_survival/map_region.h"
 #include "wave_survival/weapon_inventory.h"
 #include "wave_survival/weapons/revolver.h"
 #include "wave_survival/weapons/rifle.h"