These are groups that are not signatories to the Treaty and general enemies of civilised organisations. Opportunities to be involved with them may arise in play. You don’t find them. They find you. The Refs may also have DPC roles available for these groups. A DPC is a “Directed PC”. You will be given certain instructions and backstory details by the Refs.
The Arrangement started out as a deal between three gangs in the Hegemony capital of Cranford, where they agreed to stay off each other’s turf and collaborate in their efforts to avoid or subvert the law. The Arrangement’s people often claim that followers of Builder and Aspirant were involved in this plan, in an attempt to give it a veneer of legitimacy. They’re almost certainly right. However it started, the Arrangement adopted a “Join or Be Conquered” strategy that was a crooked reflection of the Hegemony it soon expanded across. Now, “officers” of the Arrangement keep a guiding hand on illicit activities across the Continent, and see a fine chance to get what people want, what they… need, into or out of Mat Sellah. One way or the other. They have been implicated in kidnappings of Faction agents, smuggling and other major crimes on Mat Sellah.
One of the earliest Guilds. Since then they fell on hard times, all the top people sold out to Hellions or got shanked by the Hellion cultists. They have been supplanted by the Guild of Physicans as the legitimate trade union, and the Barber-Surgeons are now wholly a Stranger cult known for their ruthless ambition and widespread network of bribery and corruption. They see the lost treasures of Mat Sellah as power to be fed to their Strange masters, and its scattered villages as a convenient source of sacrificial victims nobody could possibly miss.
Originally a Mages' Guild subgroup interested in the use of fire as a Paradigm, they created a shared, contagious Paradigm that they infect others with by the use of curses and tainted spells. They are destructive, persistent and fearless, consumed with the desire to spread their ideas and burn or recruit all opposition.
Since the surrounding reef is accessible to individual smallish ships but not entire fleets, the Mat Sellah archipelago is prone to pirate attacks. Of late, the major threat has been from an individual known as Big Jimmy.