Caribbean Sea, 1713 CE is a gameplay feature from the Campaign Mode in Assassin's Creed: Rebellion, and was released 22 June, 2021. Made up of a repeating cycle of missions styled as a Helix Rift Event, they follow Edward Kenway and the crew of the Sea Dog's Bite as they recover Groggy Bill's captured ship from a rival group of pirates.
Completing the levels rewards players with DNA fragments for any two of the six exclusive Heroes, with difficulty increasing as players beat successive entries. Notably, however, a player's roster for a single completed mission will be locked from further use in the campaign, encouraging players to quickly level up their other heroes and to maximize the abilities of what heroes they have in order to earn as many DNA fragments as possible.
As an additional difficulty, all heroes are required to survive the mission, else it will be automatically failed. Heroes can be unlocked for future use in the campaign by spending Sync Tokens, though the mission will have to be replayed with a new roster and the Sync Token cost will rise with every successive desynch.