I am working on a huge sandbox for my next campaign, and I am fleshing out some thieves guilds and assassins guilds. Additionally I made a few more organizations for players to get caught up in, and I thought I would share them. Obviously this sort of thing is very deeply tied into the campaign world, but hopefully this will serve as inspiration for your own campaigns. This is a fresh first draft, so its still very much a work in progress (and in editing). I was thinking of expanding on the Court of Love - since noblewomen often run the household members, would recieve a bonus when attempting to collect on letters of credit.
Knighthood, and knightly orders
Knighthood is a crucial aspect of Tencter social and military organization. Tencteri knighthood is earned through a long period of training, typically beginning in childhood. Elven knighthood is derived from joining one of their knightly orders. Both are united by their adoration of the goddess graiae. It was Graiae who dictated the laws of chivalry which all knights are to follow. Knights are expected to: be courteous and respectful, as guests and hosts, be courageous, though not to the point of foolishness, observe truces, seek worthy challenges, and protect the defenceless. Tencteri knights take additional vows of loyalty to their king and feudal lords, additionally they are expected to have a unique heraldic device.
Elven knights are sworn to one of two knightly orders: the order of the swan, and the order of the radiant stars. Knights of the swan serve as elite boarding crews on elven galleys, and the swear an additional oath to never let another elven city fall into ruin. Their device is a stylized swan on an azure field. Knights of the star wander deep inland, seeking out and destroying threats to the elves before they can arise, which is their vow. Their device is a white, radiant, star trailing three smaller stars on an azure field.
Knighthood is a prestigious title, and knighted PCs can speak to the nobility on roughly equal terms, allowing them access to social spheres not normally open to the grimy rabble. Players may begin play as impoverished knights. Because knighthood is martial in nature, knights that are unable to fight with a variety of weapons, and wear at least mail armour, are quite rare.
Court of Love
The court of love was first established by queen Joveta as a group for her friends friends to discuss issues of courtly and chivalric love. It has been expanded in scope and power over time, and now serves as means to mediate domestic and dynastic disputes among the nobility. Membership is freely extended to all Tencteri noblewomen, and visiting foreign noblewomen. Members may claim sanctuary at the house or castle of any lord, or at any convent for a period of forty days.
The poor brothers of St. Walaric
The poor brothers of St. Walaric are a Paucer sect of wandering mendicants. Originally they were meant to provide an orthodox alternative to the egalitarian heresies of the Frateri, but they ended up fomenting revolt as much as they defused it. For every devout brother wandering the world easing the burdens of the layfolk there are two charlatan pretenders, hawking forged indulgences and giving blessings in improvised Old Tencteri. The brothers are required to take vows of chastity, duty, and poverty. They may only own one set of clothes, and whatever set of tools or arms that they need and can carry themselves. The vow of duty obliges the brother "to work tirelessly, in whatever way he is best able, whether plowing fields, tending the sick, or slaying beasts, for the betterment of the world and the greater glory of Dux Ordus". Brothers radiate a meek holiness, granting +2 to reaction rolls. Further, monasteries are obligated to provide them free shelter and meals. Among among the Tencter, brothers are often gifted donations of food, clothes or hospitality by devout laypeople. Knights who join the brothers are especially looked up to. They follow the same rules as regular brothers, save they are still titled "sir", and they may keep two horses. They give up their heraldic devices, wearing flat brown instead.
Thieves and assassins guilds
Due to their secretive and illegal natures, there are a myriad of thieves and assassins guilds throughout Ibea, this list is meant only to provide a glimpse at a few of the largest guilds. Unlike a normal craft guild, criminal guilds do not extensively regulate their own behaviour. Thus a thieves guild is not above a little murder for hire, and assassins guilds don't mind the occasional spot of breaking and entering – as such they do not have a class requirement. Players may choose to start as members of these guilds.
The Pious Apprentices' Association is the most publicly visible of all Tencter thieves' guilds. Masquerading as a social club for poor craftsman’s apprentices, they have a reputation for helping the urban poor and lavish participation in town festivals and mystery plays. Beneath the facade the association engages in a great deal of smuggling, extortion and racketeering. Violent petty crime is generally seen as low class and foolish within the guild, unless the payout is considerable.
The association levies a 10% protection tax on all their members' earnings (including adventuring, and anything they fence), in exchange the guild offers fences wherever they have a presence (selling limits are tripled, to a minimum of 50 gp). Attempts to skirt the tax are common, and known precursors to tragic accidents.
The Silken Pursers are a thieves guild that rose up out of the hordes of migrant labourers roaming Ibea. They have always specialized in targeting the wealthy, and are notable pickpockets. More recently they have begun to associate with the frateri, gathering intelligence and supplying them money in exchange for the occasional convenient disruption or riot. The pursers do not levy a membership fee (membership is largely informal) instead usually gathering donations whenever they meet. Travelling as often as they do, guild members hear a lot of rumours, and can usually tell (90% chance) which ones are false.
The Lampblacks are a hybrid thieves/assassins guild. The guild arose out of professional thieves assassins and spies, and are often viewed as the secular arm of the sons of nul. They pride themselves on craftsmanship and technique. Consequently, their tools are notoriously good, Thieves' tools made by the lampblacks are the best on the peninsula – providing a +2 bonus to any rolls made using them. By tripling their base cost the tools can be worked into a functional mundane item such as the handle of a dagger or the cover of a book. The lampblacks also produce lampblack, for which they are named. A greasy matte brown-black paste, lampblack is used to darken the skin, providing a +4 bonus to attempts to hide in shadows. However it is highly flammable (fire damage is doubled while wearing it), and it irritates the skin, causing weeping hives and acne (-2 to reaction rolls for one week after using lampblack). A one use pot of lampblack costs 10gp. Lampblack membership is a steep yearly fee – 100 gp per rank (level). Because of their amicable relationship with the Sons of Nul, in cities where both guilds have a presence, members of the lampblacks may purchase Sons of Nul poison.
The Sons of Nul are an assassins guild devoted utterly to the god Nul. In many ways they are more like a church than a guild – money is not especially important to them, and their meetings and customs are steeped in religious meaning. Since many of these rituals are based around darkness, sneaking, and working in secret, guild has reputation for infiltration. Generally the Sons of Nul are on good terms with the Lampblacks, due to their mutual admiration of sneaking about, and guild members may purchase lampblack thieves tools in towns with both guilds. The guild is also particularly good with poisons, poisons purchased from, or made by, guild members impose a -2 penalty to the victim's saving throw. They can also concentrate poisons, doubling their effect while tripling their cost. Membership fees to the Sons of Nul are paid in secrets, or in particularly daring feats of stealth. The value of the secret and danger of the feat must be relative to the skill of the member. Thus a novice might reveal the true parentage of the town smith's son, while a master might be required to sneak into a castle undedected. While membership to a criminal guild is obviously illegal, membership to the Sons of Nul is usually apostasy. If a confessed member of the sons can be proven to have been raised in the church then they are burnt at the stake, whatever their other crimes.
The Black Tusks are a relatively new assassins guild, concentrated mostly in the north of Ibea and in the Barwonslaw. Their name references the orcish habit of blacking their tusks before a night raid. They are notoriously brutish and violent. Notably, they openly accept half-orcs as equals, and half-orcs make up a large portion of their membership. They have deep ties with the arena at Dok, where they make their headquarters. Often their victims will be kidnapped and forced to fight and die in the arena. The tusks have struck a deal with an Amastag merchant prince to act as their fence. His agents in Dok will buy up to 10 000 gp a month from guild members, at a 20% penalty. The guild attracts the violent and desperate, and any town with a guild presence will always have 1d4 1st level assassins available for hire. Membership is a flat 10% tax off the top of any money the member makes. Those who are caught underpaying usually bleed out before their former guildmates can think of a clever punishment.