The Rise of the Swift was a thieves guild of ill repute, formerly based in Arborea and later based in the Outlands. They were subservient to the Society of the Black Lotus, mostly due to their leader, Raven DuBois, also being a member of the Society's inner circle.
70 years in the past, the Swift came after Cal's parents to avenge his theft of their membership brooch. His father was kept in a remote prison in Carceri called “The Red Pit” on Raven DuBois' orders until he was rescued by the Planeswalkers. His mother, sadly, did not survive the initial assault by the Swift.
Upon being rescued, Cal's father told the story of the Swift's origins, explaining how they were corrupted and subverted to evil by Raven's treachery.
With the Black Lotus' help, the Swift nearly entered into an accord with the Tiger's Claw to smuggle contraband through their territory in Sigil. It was only after the PCs exposed their contraband as captured slaves that the deal fell through.
Later, a slave-capturing operation based out of a derelict manor in the woods near Sylvania was shut down by the Planeswalkers, the members within either killed or turned over to the nearby Gate-Town for punishment. Raven DuBois herself was defeated in Carceri, and the guild is presumed defunct, though the larger threat of the Black Lotus remains. (The story so far)
Members
Lady Raven DuBois
Associates
Lord Pendleton