The Tattered are driven by hatred. All their lives they have done without, and given a chance to close in on those who ‘have’ they kill with disturbing intensity.
The Darkness is not a group of assassins. They are however, not friendly people.
First he becomes sweaty and feverish. Then the boils begin. The boils are beautiful. After that, he finds it difficult to breath, then move, then he drowns in his own blood. Is that sufficient?
The Strangler is a chaos entity worshipped by an assassin cult. Using narcotics in their worship members of this killing cult are very very dangerous.
Then all of a sudden, the victim gets convulsions and seizures, eyes bulging and mouth foaming.
“Sigh. Another mysterious, highly skilled assassin, with a difficult child hood and black clothes. Oh. This one has knives in his belt, not his boot. Well, at least it is not a Drow. ”
A group of highly educated rich youths and nobles that have a desire for a darker side of life. While the King’s Paupers are from the veins of the rich and noble, they are far from the same attitude of their fathers and the court. They took the name the King's Paupers in jest to the way their life was.
Once a great monarchy flourished and the royal Kings and Queens were buried in booby-trapped barrows with treasure and with Undead servants to watch over the tombs. The religion changed over time and the monarchy was running out of money, as the kingdom’s wealth was being tied up in ancient tombs. Something had to be done.
Perhaps they lack the subtlety of other groups, but the Candles of God have no desire to be subtle. Perhaps they do not keep their secrets very well, but the Candles of God want their voices to be heard. Perhaps they are careless about who they kill, but there shall be no innocent bystanders when the fires of hell consume the unrighteous.
The King’s Hands are a secret espionage group. These agents secretly support the Crown, feretting out traitors, investigating military and political manuverings of other countries, stealing copies of plans and spells that would unbalance the status quo, and in short, making the world safe for good decent people and the Crown that supports them.
The principal axiom of the Curalon Hestaris, and the basis of all its teachings, is this:
"Inhale. Kill. Exhale."
The Liberators of the Coin is primarily an organization Halflings devoted to (insert trickster/thieving/Halfling god). They pattern themselves after a myth of the god stealing gold coins from his brother on the evening of his wedding. The stolen gold was a part of the wedding ceremony and its absence meant that the ceremony could not proceed. The theft resulted in the trickster being able to marry his brother’s intended.
The Hand are assassins and spys of legend. Each member has super human abilities and skills. They have been known to breach the tighest security. They have been implicated in hundreds of deaths, though no proof of foul play has been found for many of them. However, things are not always what they seem… especially when an Orb is around.
If you want to add a "supernatural" touch to your campaign, define the rules of magic and the universe. Make your players comfortable with those rules. Then your new supernatural creatures must then break those rules.