SRD:Wounding

Wounding: A wounding weapon deals 1 point of Consitution damage from blood loss when it hits a creature. A critical hit does not multiply the Consitution damage. Creatures immune to critical hits (such as plants and constructs) are immune to the Consitution damage dealt by this weapon.

Moderate evocation; CL 10th; Craft Magical Arms and Armor, mage’s sword; Price +2 bonus.