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 large amounts of lightning and sonic damage per proc (approximately 1600 each, see: Talk: Stormreaver's Thunderclap).

Does not scale with the user's spellpowers. Does scale with most things which would effect most elemental damage on weapons, such as helplessness, vulnerability, MRR reduction, doublestrike, melee alacrity etc. Unknown if this scales with expanded vorpal range.

Only the sonic damage is reduced if the target saves; the electric damage is unaffected.

Unlike many on-vorpal effects, may be stopped by fortification checks.

Procs after the helpless effect from Balanced Attacks, so if used in combination with that ability, it will always benefit from helpless damage boosts resulting in much larger hits (5k+), except where enemies are immune.