History of Storm Grenade

Overview

The Storm Grenade is an Arc grenade that calls down a focused lightning storm. It is one of the seven grenade abilities available to all Arc subclasses, used by Stormcaller Warlocks, Arcstrider Hunters and Striker Titans.

Effects

After a 0.7 second delay, the grenade drops a bolt of lightning, followed by a bombardment of 12 smaller bolts in an X pattern. The bombardment lasts 1.6 seconds in total.

Synergy

Rising Storm recharges super, grenade and melee energy, and Crown of Tempests increases the recharge rate of Arc abilities when Arc kills are made. With the Touch of Thunder Aspect, the grenade also leaves a roaming thundercloud after detonating that fires lightning bolts at nearby enemies.

The synergy section of the D2 Wiki page predates Arc 3.0, so those details may be out of date.