The game's setting spans the West Indies with the three main cities of Havana, Nassau, and Kingston, along with numerous islands, sunken ships, and forts. Multiplayer also returns, albeit with only land-based modes and settings. Unlike previous games, gameplay elements focus more on the ship-based exploration of the seamless open world map, while also retaining the series' third-person land-based exploration, melee combat, and stealth system. A major plot element concerns the attempted establishment of an independent Pirate republic in the Caribbean. The main story is set in the West Indies during the Golden Age of Piracy from 1715 to 1722, and follows notorious Welsh pirate Edward Kenway, grandfather of Assassin's Creed III protagonist Ratonhnhaké:ton / Connor and father of antagonist Haytham Kenway, as he searches for fortune and a mythical location called the Observatory, which is sought by both the Assassins and the Templars. The framing story is set in the 21st century and depicts the player as an employee of Abstergo Industries (a company used as a front by the modern-day Templars), who is manipulated into uncovering secrets related to the Assassin-Templar conflict and the precursor race known as the First Civilization. The plot is set in a fictional history of real-world events and follows the millennia-old struggle between the Assassins, who fight to preserve peace and free will, and the Templars, who desire peace through control. The game was released for Google Stadia in September 2021. It was later ported to the Nintendo Switch as part of The Rebel Collection alongside Assassin's Creed Rogue in December 2019. Black Flag was originally released for PlayStation 3, Xbox 360, and Wii U in October 2013 and a month later for PlayStation 4, Windows, and Xbox One. Its historical timeframe precedes that of Assassin's Creed III (2012), but its modern-day sequences succeed III 's own. It is the sixth major installment in the Assassin's Creed series. Assassin's Creed IV: Black Flag is a 2013 action-adventure video game developed by Ubisoft Montreal and published by Ubisoft.

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