Nightwatcher

Nightwatcher was a unique, black +3 longsword that revealed darkness and those of ill-intent.

Description
This unique weapon had a razor-sharp blade of black adamantite and a pommel made of silver and ivory with a pommel inlaid with a black pearl. Unlike many magical weapons, it radiated no light.

Powers
The +3 longsword allowed its wielder to see at night, just as well as if it were the middle of the day. It dispelled all magical darkness within 30' (9.1m). When the sword was plunged into the ground, it hummed loudly and revealed anyone who wished its wielder any harm, though it did not illuminate any astral or ethereal creatures.

History
The first rumored resting place of Nightwatcher was within an ancient ruin in the Anauroch desert, found by a grizzled adventurer who traveled the Sword Coast in the 12 century DR. On the day of his eldest daughter's wedding, the adventurer gifted the sword to her fiancé. It was then passed down for the next four generations until it was sold to pay off gambling debts.

Over the next 50 years, Nightwatcher popped up sporadically around Faerûn until it came into the possession of an exceptionally eccentric adventurer, who was eventually killed by trolls some time in the 1330s DR. No reports of the sword have appeared ever since.