Nightwatcher

Nightwatcher is a +3 long sword with a black blade and a silver and ivory hilt set with a large black pearl. It does not radiate light, but the wielder can see outdoors at night as if in broad daylight. If thrust into the ground, it will hum loudly if an enemy approaches within 60 feet, even if Invisible. It dispels magical darkness within 30 feet as a Dispel Magic spell cast by a 15th level mage once per day.