The Dragonslayer is Kliff Undersn's signature weapon.
It is a large blade which was forged from the scales and fangs of a dragon. It also retains the essence of the dragon whose blade it was created from as well as the spirits of the dragons that were slain by it. It is Kliff's only known weapon throughout the Crusades. Judging from artworks of a young Kliff, it's most likely that the sword was his weapon for more than 60 years until the time of his death in 2180. It is said that it had the ability to channel and amplify one's Ki.
The Dragonslayer is the largest known sword in the series with a blade (approximately) 5-6 feet long and 3 feet at its widest.