update

scripts/enemy/enemy.gd

@@ -13,6 +13,7 @@ func _ready() -> void:
   spawn_position = global_position
   add_to_group("enemies")
   EventBus.entity_died.connect(_on_entity_died)
+  EventBus.damage_dealt.connect(_on_damage_dealt)
 
 func _on_entity_died(entity: Node) -> void:
   if entity == self:
@@ -26,10 +27,29 @@ func _physics_process(delta: float) -> void:
     velocity.y -= gravity * delta
   move_and_slide()
 
+func _on_damage_dealt(attacker: Node, damage_target: Node, _amount: float) -> void:
+  if damage_target == self and attacker.name == "Player":
+    _engage(attacker)
+
+func _engage(new_target: Node3D) -> void:
+  if state == State.CHASE or state == State.ATTACK:
+    return
+  target = new_target
+  state = State.CHASE
+  _alert_nearby()
+
+func _alert_nearby() -> void:
+  var enemies := get_tree().get_nodes_in_group("enemies")
+  for enemy in enemies:
+    if enemy != self and is_instance_valid(enemy):
+      if enemy.state == enemy.State.IDLE:
+        var dist: float = global_position.distance_to(enemy.global_position)
+        if dist <= 3.0:
+          enemy._engage(target)
+
 func _on_detection_area_body_entered(body: Node3D) -> void:
   if body is CharacterBody3D and body.name == "Player":
-    target = body
-    state = State.CHASE
+    _engage(body)
     EventBus.enemy_engaged.emit(self, body)
 
 func _on_detection_area_body_exited(body: Node3D) -> void: