Sword of Kahless

First bat'leth ever forged, forged in the 9th century

Kahless created the sword by dropping a lock of his hair into a river of lava, from Kri'stak's summit;

Then cooling the burning lock in the Lake of Lusor & forging it into a blade

Using it, he slew Molor, conquered the Fek'Ihri, & created the first Empire

Stolen 500 years later by the Hur'q, lost to the Klingon people