The subtitle of the fourth major game is Black Flag.
Assassin's Creed IV: Black Flag was released in 2013 and follows Edward Kenway, a Welsh privateer who becomes involved with the Assassin-Templar conflict. The game is set primarily in the Caribbean during the Golden Age of Piracy, with locations including Havana, Nassau, and Kingston.
Black Flag expanded naval exploration into a central part of the experience. Edward commands the ship Jackdaw, gathers resources, attacks vessels, and explores islands and underwater sites. The game also features historical pirates such as Blackbeard, Charles Vane, and Anne Bonny.
The subtitle is often confused with Rogue, another sea-focused Assassin's Creed game released in 2014. Rogue follows Shay Cormac and presents the conflict from a different perspective. Black Flag's defining combination of open-sea travel, piracy, and Edward's character arc distinguishes it from the later nautical entry.