The Duke of Zephyrs

The Duke of Zephyrs is a wind serpent, and one of the Elemental Nobles of the Abyssal Council. The Cenarion Circle believe that he and the other three Dukes are the primary force behind the organization of the Twilight's Hammer Cultists in Silithus. Its relations with Anshal and Asaad are unknown.

Summoning

The Duke of Zephyrs does not appear normally in the standard plane of existence but must be summoned. There are two ways of summoning the Duke:

Acquire a set of Twilight Trappings and a [Twilight Cultist Medallion of Station]. This will make you appear to be a middle-ranked leader of the Twilight's Hammer. Travel to a Wind stone and use it to summon a Duke. You have a 1 in 4 chance of summoning the Duke of Zephyrs.
Turn in Encrypted Twilight Texts to Hermit Ortell. He will then mail you a random item. If you get a [Scroll: Create Signet of Beckoning], you can combine that with a [Dark Rune] and 5 [Elemental Air] to create a [Signet of Beckoning: Thunder]. This signet can be used to specifically summon the Duke of Zephyrs.

Enveloping Winds — Surrounds an enemy with a cyclone for up to 10 sec. If the target takes any damage, it will break free of the imprisoning winds.
Forked Lightning — Inflicts Nature damage to enemies in a cone in front of the caster.
Lightning Cloud — Creates a cloud of lightning that lasts 14 sec., blasting all enemies in a selected area for 788 to 1012 Nature damage and inflicting 963 to 1237 additional damage every 2 sec.
Wing Flap — Strikes enemies in a cone in front of the caster, knocking them back.