Stormreaver's Thunderclap

Stormreaver's Thunderclap: This item crackles with power, flickers of lightning emenating (sic) from it. On a Melee strike of a Natural 20 that is confirmed as a critical hit, this item will strike your foe with a tremendous burst of lightning. A DC 100 Reflex save will prevent half this damage.

Deals approximately 1600 lightning damage per proc (see: Talk: Stormreaver's Thunderclap. Unlike many on-vorpal effects, will be stopped by fortification checks.