Darkstorm is a Hex in Dark Souls 2. To cast a Hex, you must use a staff/chime or Special Weapons that can cast Hex.
"An esoteric spell created by Navlaan, the infamous exiled sorcerer.
Creates a local vortex of dark flame.
The heretic Navlaan was executed along with his entire village, and the mere utterance of his name became a crime. Some say it was because he sought to restore the banned art of resurrection.
Catalyst: sacred chime"
- A vortex of black flame with orbs of darkness (similar in appearance to the orbs the Affinity spell) will begin to circle around your character and spiral outwards, dealing damage to those it comes into contact with. Knocks down certain enemies.
- Hex version of Soul Vortex, although the orbs circles the caster around instead of having the vortex be projected out.