Throwing spiders

Throwing spiders are metallic weapons with extremely sharp edges and stylized as spiders. Before leaving the Underdark, Liriel Baenre used to visit Zz'Pzora's lair, which was a powerful Faerzress. She would then leave several items for some time in hopes of said items absorbing some of the magical emanations of the Faerzress. In the case of the throwing spiders, they became superrnaturally sharp, capable of digging into wood and even stone with ease.

“''To buy a moment’s time, Liriel hurled a throwing spider at the hideous golem. The magic-enhanced weapon bit deep into the creature’s throat. It would surely have killed a living creature; the golem had no blood to shed. It bared its fangs and kept coming.''”

Extract from: Elaine Cunningham. “Starlight and Shadows #01 - Daughter of the Drow”.