private void OnTriggerEnter(Collider other)
 {
     // if colliding with enemy action collider change to combat state
     if (other.gameObject.CompareTag("Action_Collider") && other.transform.parent.gameObject.CompareTag(_tag))
     {
         Troop _thisTroop = _parentGameObject.GetComponent <Troop>();
         _thisTroop.currentTarget = other.transform.parent.gameObject.GetComponent <Troop>();
         _thisTroop.ChangeState(new Combat(_thisTroop));
     }
 }