Ethereal

The Original Concept and WoW are Property of Blizzard.

Wandering chaos and void alike between Universes, the Ethereals are mostly nomadic; although, they have several City Domes built all over the known Universe...And probably more in the obscure portions of reality.

Ethereals are focused almost entirely on trade, and deal largely in arcane, abstract objects. The vast majority of Ethereals are liars and scoundrels, caring not for good nor evil so long as they can turn a profit at the end of the day. However, though rare, there are Ethereals who are decidedly kinder to their customers...

Masters of arcane spellcraft, Ethereals have incredible magical ability. Their politics are also built on money and trade; lead by Trade Princes and political "companies."

Origins
The Ethereals originated from an alternate universe, on a largely desert planet. However, their planet was assaulted by a world-devouring being similar to Unicron. They managed to escape on their cityships, but their physical bodies were torn asunder, leaving wraith-like beings. However, once they learned to bind themselves in enchanted cloth bandages, the Ethereals found that their magical ability was far, far greater than before. They are currently spreading through the Original Universe.

Trade Princes & Companies
Trade Princes are merchants who have gained the most riches and influence, and thus are recognized for both this and an ability to lead. Unfortunately, most are constantly attacked by assassins. Rather similarly, their companies consist of huge numbers of merchants allied to gain leeway in political affairs, which are represented by their leaders in all Ethereal councils.

Other "Professions"
For Ethereals who don't wish to bother with the intricacies of trade and politics, another option became clear: A significant number of Ethereals simply steal what they want. No Ethereal thief is 'petty'; they'll never go for a simple mugging. Instead, they're known for banding together in large numbers in order to acquire what they want. Some commandeer ships; some orchestrate elaborate scams; and some, even hated among other thieves, specialize in robbing temples and tombs.

Trivia

 * The Ethereal language and its sub-languages are largely based on Arabic.