St. Aeldred was one of the Three Missionaries to the Dwarves and a fierce foe of evil. After his death he left behind not just relics but a legacy of protecting the weak and fighting the undead. Priests dedicated to his cause created a handful of magic items that resemble one of his his relics, the Apsergillum of St. Aeldred.
An Aspergillum of the Guardian looks like any well-made aspergillum constructed of oak and silver. A Good cleric or religious brother, however, can call upon the Aspergillum to dispense a splash of holy water. This holy water will strike any single target within 60' of the wielder automatically and can even strike undead that are largely within the Ethereal plane (such as ghosts) as though there were wholly material. The being struck is drenched with enough holy water to have double normal effect, if any. A Lawful Good cleric or religious brother may use the Aspergillum up to three times a day, all other Good priests may use it only once a day.