In Assassin's Creed Syndicate, Jacob and Evie Frye lead a gang called the Rooks.
The Rooks are formed in London by the Frye twins after their arrival in the city during the Industrial Revolution. Jacob recruits and organizes the gang to challenge the Blighters, a rival group controlled by Templar influence. The Rooks support the Assassins by fighting enemies, controlling districts, and helping civilians.
Gang management is one of Syndicate's distinctive systems. The player can upgrade the Rooks and recruit additional members, improving their effectiveness in street battles and city activities. The gang therefore functions both as a narrative faction and as a gameplay progression system.
The Blighters are the principal rival gang, not the answer. The Frye Gang is an informal description sometimes used by players, but the canonical name is the Rooks. Syndicate was released in 2015 and is set in London in 1868.