Cormac is the surname of Shay, the protagonist in Assassin's Creed Rogue.
Shay Patrick Cormac begins the game as an Assassin operating in the North Atlantic during the Seven Years' War. After a disaster connected to an attempt to recover an ancient artifact, he becomes disillusioned with the Brotherhood and joins the Templars.
Rogue is notable because it places a former Assassin in the role of a Templar-aligned protagonist. Its story fills part of the gap between Assassin's Creed IV: Black Flag and Assassin's Creed III, while also connecting with characters and events from both games. The North Atlantic, the Hudson River Valley, and New York are important areas.
Shay is sometimes incorrectly identified by a Kenway surname because the game features Haytham Kenway and other characters from that family. Kenway is not Shay's family name. His full name is Shay Patrick Cormac.