From the announcement:
Fantasy Flight Games is proud to announce that in the sixth wave of starship expansions for X-Wing™ the galaxy’s Scum and Villainy will join the game's fast-paced space battles as its third faction!
The ranks of the Scum and Villainy faction are filled with many of the Star Wars galaxy’s most notorious bounty hunters, pirates, and Black Sun agents. You’ll find such infamous figures as Boba Fett, IG-88, Greedo, and Prince Xizor. These Scum live outside the law, do their best to remain at the periphery of the ongoing Galactic Civil War, and allow no one – no one – to threaten their profits.
Whenever Rebel or Imperial forces dare to interfere with their illicit dealings, Scum head to battle, and they do so in some of the best starfighters that money can buy, such as Slave I, IG-2000, and the MandalMotors StarViper-class attack platform. These expensive and technologically advanced starships are further supported by a number of mainstays that have proven their efficiency over the course of numerous battles.