Lightning Quake (Rogue passive)
What does it do exactly? it doesn't change anything, description says "enhanced version of Lightning Ball. Press tab when EX power bar is full", but you get it so early in the game so I think it's a mistake in the description. There's no such passives for any other EX skills, you just get them automatically. Doesn't have anything to do with long press Lightning Ball, that's just something you get once you turn into Wolf Guardian.
Can anyone shed some light please?