Ubisoft has introduced a new progression system to Assassin's Creed IV: Black Flag, titled 'Black Flag Resynced,' which includes daily quests and a battle pass-like mechanic that grants Data Fragments. These fragments can be exchanged for cosmetic items and keys to unlock content from other Assassin's Creed titles. This system is similar to one previously implemented in Assassin's Creed Shadows.
To earn Data Fragments, players must have the 'Eyes in the Dark' project active, which ensures rewards are applied to Black Flag itself. The primary method of acquiring these fragments involves completing anomalies that appear around the game's Caribbean setting. These activities become available after completing Sequence 4, which involves securing Great Inagua. Players can access a log of available anomalies by opening their map and pressing the designated button for the quest log.
The types of anomalies vary depending on the currently active Animus project. Generally, these tasks are straightforward and include objectives such as sinking corrupted ships and convoys, or completing short puzzle segments like rifts. Successful completion awards a set amount of Data Fragments, which can then be used to acquire rewards from the active project track.
Rewards from the Animus project exchange can include new cosmetics and weapons. Crucially, players can also obtain keys that allow them to purchase items themed around other installments in the Assassin's Creed series. New anomalies become available on a timed basis, indicated by a timer above each one, meaning players must wait for existing anomalies to be replaced once completed.