The Orrdash Horde moved quickly, but not as quickly as the Tyralic Order of Wizards. The wizards communicated the direction of the horde’s advance and coordinate the response of the Vendian Baronies so that they were not overrun piecemeal. When asked how they knew what the horde was doing, the wizards replied, “We see father than mortals.”
Communicative Mirror
These devices are constructed to facilitate rapid communication among magical orders. They usually take the form of a wall mirror though hand mirrors are popular among adventuring wizards marked with a runic mark at the very least and many are ornately decorated. Each of these items is keyed to either an owner or a location (such as the Guildhouse of the Order of Night in Viant) by use of the arcane mark spell.
Sea of Stars RPG Design Journal 