Ancient Painblade

This antique weapon is the traditional precursor to the modern day's Painblade.

In ancient times, Jin-Mei soldiers riding to the field used to plunge their swords into filth, in the well-founded expectation that the wounds they inflicted would cause infection and rot. This nasty tactic was given new life when royal technicians (in those days referred to as Nuyin, something akin to "wizards") developed a blade whose surface, when unsheathed, swiftly attracted and encouraged bacterial growth, giving life to all kinds of deadly filth.

Nowadays, these items are mostly used in theatrical plays, and anyone who gets within a hand's reach of their swinging blades usually spends half an act wailing about it before finally dropping dead.