Lightning Strike

Effect: This Weapon stores the power of a volatile thunderstorm deep within. Occasionally, this dynamic power comes to the surface, devastating enemies with a massive lightning strike.

Found on: (18) Lightning Strike items:

Notes:

1.5% chance to strike with Lightning. 20d20+400 damage (610 average strike, 9.15 average hit)

Quote:
Originally Posted by (former developer) Eladrin Lightning Strike on weapons is 1.5% application probability, and is indeed 20d20+400 electrical damage.

Found also on:

Green Steel weapons
Loot-gen weapons as Dynamo

Lightning Storm Guard

Effect: This item stores the power of a volatile thunderstorm deep within. When the wearer of this item is successfully attacked in melee, this dynamic power occasionally comes to the surface, devastating enemies with a massive lightning strike.
Found on: (2) Lightning Storm Guard items:

Notes:

On-Being-Hit 1.5% chance to strike with Lightning. 20d20+400 damage (610 average strike, 9.15 average hit)

Sovereign Lightning Strike

Effect: This item crackles with power, flickers of lightning emanating from it. On a 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 of this damage.
Found on: (3) Sovereign Lightning Strike items:

Lightning Strike