Banshee Blade

This screaming blade can kill its victim even before they feel its keen edge.
Pick one of the bearer's melee weapons to be
a Banshee Blade. Each time you roll a hit roll
of 6+ for this weapon, roll 2D6. If the roll is equal to or more than the target's Bravery characteristic, that attack inflicts D3 mortal wounds in addition to its normal damage.