Black Spear

From Glen Cook Wiki

This magical weapon was crafted by One-Eye during the seige at Dejagore, when half of the Black Company spent months trapped in the city by the Shadowmaster Shadowspinner. The spear is long, heavy, and ebony, with intricate characters and inlaid silver designs. At times, especially when a likely target is near, its surface is covered with "crawling worms of silvery light" and the head glows. One-Eye initially says it is designed to kill the Shadowmaster. It does prove a potent weapon, though it doesn't hit its mark in that battle.

Over the next twenty years One-Eye continues to enchant and modify the Spear, until it becomes his life's sorcerous masterwork - one of the most powerful magical weapons in the Company's possession in fact. It is capable of dealing terrible wounds to creatures normally invulnerable to weapons, such as the forvalaka and Goblin when he is possessed by Kina.

Eventually, the Black Spear is actually used to kill Kina, in conjunction with an exploding Voroshk flying post. The weapon survives even this conflagration, with only a little damage to the metal inlays.