How To Use Chain Lightning?

So i recently found out that if i put tier 4+ powders on my weapon i get something called chain lightning, however, i have no clue as to how i can use it... Any help?

 

Hit around 10 mobs with your weapon that you powderified, and a Thunder symbol should appear on your screen. Shift and left click a mob to activate the special.

 

depends on attack speed

 

When you put two t4 or higher powders of the same element on an item you get a special. It charges as you hit mobs with melee attacks and when it reaches 100% you sneak and left click to use it.

 

Ok thank u all for the responses and now i know how to use this and not waste my ability, thx :D