Mariella was sent by Cardinal Innocent to kill the bearer of the Darkness, Jackie Estacado. Her mother, Rosalia, the previous Magdalena, had only just died, and so Rosalia was sent out into the field ahead of schedule with incomplete training. Her first encounter with the Darkness wielder ended in disaster and resulted in the Spear of Destiny being broken. Three other sisters from the Order of the Magdalene came to assist her, but the Darkness still emerged victorious.
Mariella managed to recover from the ordeal and received word that the Spear was in a secret location in the Amazon jungle. Upon traveling to the Spear's location in order to retrieve it, she ended up facing the Angelus, Lauren Franchetti, as well as her daughter Appolonia who wielded the Spear and chose to use it for darkness. As the battle progressed, the Magdalena was able to prevail against the Angelus' warriors but could not gain the upper hand against the combined forces of the Angelus and her daughter. Lauren then chooses to give herself completely to the Angelus entity and rather than choosing to face her daughter for embracing the Darkness, she flees from the battle. Mariella apparently survived the confrontation and was successful in recovering the Spear.