Blade of the elements

The blade of the elements was a magical katana from Kara-Tur that appeared in Faerûn in the 14th century DR.

History
Lord Sunang of Kara-Tur was forced to make alliances and purchase magical weapons like the blade of the elements when his lands were besieged by the forces of a mighty wu-jen. However, this strategy proved very costly: Sunang was near-bankrupted and his influence waned, while his enemy continued to grow in power. Ultimately, Sunang's realm collapsed from its own weaknesses, not to conquest. It was supposed that the profit-hungry merchants supplied arms to both sides, but proof was lost to history.

The blade of the elements may have turned up in the Sword Coast North in 1372 DR.

Description
The katana was observed to have a guard, with either a tassel hanging from the guard or a brown cloth wrapped around the lower half of the blade.

Powers
A blade of the elements was a +3 katana that could slay an elemental on impact.