the Sword of Kas was the mighty blade used by Kas the Bloody-Handed, the dreaded lieutenant of Vecna. It was by this blade, some say, that Vecna lost his Hand and Eye.
The sword,, was crafted by Vecna. The blade is said to have been magically honed to a razor's edge, enhanced the wielder's strength, and could be used to call down lightning bolts from any storm clouds that might be overhead. The sword itself is intelligent, possessing a vile and murderous spirit.
The ancient sword at some point found its way from the King's Royal Armory into the hands of Ilroth Narok who used it in his final battle at Bloodfrost where he lost his life.