Assassin's Creed Black Flag Resynced introduces 'What If' Rifts, optional Animus segments that delve into alternate realities for its characters. These Rifts become accessible as players progress through the main campaign and offer a variety of challenges, including platforming, combat, and stealth, culminating in unique rewards.

Rift #1: Wayward Souls

The first Rift, "Wayward Souls," unlocks after completing Sequence 04: Overrun and Outnumbered. Located on the southern coast of Great Inagua, this challenge presents a scenario where Edward Kenway might have kept his promise to Caroline. Players must carry a chest representing accumulated wealth, which depletes health when not held. Sections require diving into a chasm and navigating an on-rails sequence while avoiding hazards like jellyfish. Completing this Rift rewards the player with the Lock of Hair, a trinket that restores health after a perfect parry.

Rift #2: Wayward Desires

Following Sequence 08: Do Not Go Gently, players can access "Wayward Desires" north of Nassau. This Rift explores an alternate path for Blackbeard, who accepts a pardon to rule Nassau. The challenges primarily focus on combat across derelict ships within a maelstrom, featuring spectral opponents that require dodging and strategic use of swivel guns. An on-rails swimming segment through the whirlpool involves avoiding explosive barrels. The climax includes a boss fight against Blackbeard's specter. Victory yields the Queen Anne's Revenge Wheel, a cosmetic item for the Jackdaw.

Rift #3: Wayward Minds

"Wayward Minds" becomes available after Sequence 11: Everything Is Permitted, found on Sacrifice Island. This Rift considers a future where Mary Read abandons her assassin life to raise her child. It combines combat and stealth sections. Initial combat segments involve eliminating spectral soldiers, including dangerous snipers, and navigating environmental hazards. An AI entity named Ego provides guilt-inducing commentary on the player's actions. The latter half shifts to pure stealth, where players must navigate enemy patrols and spotlights without detection, culminating in a choice to "Renounce the Creed." The reward for completing this Rift is the "Don't Forget Your Old Shipmate" sea shanty collectible.

Rift #4: True Purpose

The final "What If" Rift, "True Purpose," requires completing the main campaign, the epilogue, and the preceding three Rifts. Located east of Misteriosa, this Rift poses the question of Edward Kenway becoming a Templar. The experience begins in a theater where Ego discusses alternate outcomes, leading to an interruption by an entity resembling a Jackdaw. Players must choose to "Fight Back" and clear out hostiles in the theater and backstage areas. Following this, players ascend rafters to eliminate remaining enemies. The Rift culminates in a two-phase boss battle against Ego, the Emotion Agent, who employs attacks like Whirlwind, Ground Pound, and Chaos Beam. Defeating Ego rewards the player with the Dark Animus Corsair Pistol Swords, a legendary weapon that fires two shots with a heavy strike at no ammo cost, effectively providing infinite ammunition. Additionally, players can claim 300 keys for the Dark Animus objective in the Animus menu.