The game also includes naval combat, with 40% of the story taking place on the water, which includes numerous side missions. After checking out a ship with Edward's spyglass from the Jackdaw's crow's nest and evaluating the information and statistics, players can launch an attack using various scenarios; one can simply shoot the opposing captain, board the ship by leaping from mast-to-mast and performing an air assassination, or charge into the fray to cut down foes using Edward's swords. Once the objectives for each boarding process, all of which include killing a certain amount of soldiers, are completed, the player has three options - reduce the Jackdaw's notoriety, send the ship to Edward's fleet, or salvage the ship to repair the Jackdaw. Players are also able to exploit weather patterns, luring the opposition into less than ideal conditions, such as rogue waves, to their advantage. Naval combat also features a trajectory-based aiming system that requires knowledge of distance and the speed of an enemy.
Edward awoke to find himself in leg irons together with a fellow prisoner, Adéwalé. After freeing themselves, the men rescued the fleet's prisoners and stole a brig, which Edward decided to keep afterwards. He named his new ship the Jackdaw and made Adéwalé his quartermaster. Following this, the pirate set course for Nassau. After assembling a crew, he met with Edward Thatch and Benjamin Hornigold, who took Edward out to sea to teach him how to plunder ships. He then met with James Kidd, and devised a plan to rob a plantation. Edward and Thatch set out to acquire a galleon for Nassau's defense. The pirate assassinated its captain, the Templar Julien du Casse, and claimed his vessel for Nassau's defense and his island for himself.
After retrieving his ship and crew from Rackham, Edward traveled to Kingston to learn more about the Sage's location. Edward located Hornigold and Rogers, who met with Torres. Through them, Edward learned that Bartholomew Roberts could be found on the island of Príncipe. He traveled to Príncipe, in order to find Roberts. During his search, Edward assassinated Josiah Burgess and John Cockram, freeing pirates from a Portuguese camp along the way. With that, Edward finally gained the trust of Roberts, who in turn requested his aid. Edward met with Roberts to claim a set of vials from a Portuguese fleet. They managed to acquire the blood vials, and Edward was promised a chance to enter the Observatory.
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