Witch-Lords of Rome

A secret cabal of wizards/sorcerers/warlocks lurks behind the facade of normal, mundane life in the Imperium Romanum. Far-flung across the provinces, they use magic to communicate with each other and to send their agents to distant locations. They all have their own agendas, but share common goals as well, and they regularly "lend" their agents to each other.

Fundamentally, they are fantastic, magical patrons for the adventurers, providing motivation and the means (via teleportation magic) for them to travel across the empire and beyond its borders in pursuit of common goals.

This idea was born out of the idea of trying to make the campaign truly world-spanning, with characters moving freely from one DM's domain to another's. Without jumping to the conclusion that this will ever actually happen, I will create at least one such character in Aegyptus who can send the PCs off someplace else if the need arises. It will probably be a character who was a low-level mage 20 years ago in the original campaign, possibly Chala or Kunte.