public IEnumerator FindEnemies()
    {
        GameObject[] objects = Object.FindObjectsOfType <GameObject>();
        enemies.Clear();

        foreach (GameObject obj in objects)
        {
            if (obj.tag == "Enemy")
            {
                enemies.Add(obj);
            }
        }

        if (enemies.Count == 0)
        {
            popUpController.FadeToBlack(false);
            yield return(new WaitForSeconds(3f));

            levelController.LoadLevel(1);
        }
    }