The Sword of perma-death can take multiple forms but it's common form is an rapier since it was a very fatal sword. This sword also has diseases that is unknown to medicine making this sword truly a killer. Another benefit to this sword is that It permantly kills any respawning entity... however nobody knows where it is
This weapon is only known in legends however as nobody has ever wielded this sword... according to the legends, the bladesmith's first friend, Densetsu created this weapon in rage after a determination entity had killed off his wife and children.
