Completing the main mission "Do Not Go Gently" grants players the Blackbeard's Treasure map, which leads to a buried chest in Anotto Bay, north of Kingston.

The map contains no coordinates and includes a side quest titled "Blackbeard's Treasure"; players must navigate underwater sections, avoid enemy ships, and can fast travel if they have previously visited the area.

Swim to the wooden staircase and diving bell on the left side of Anotto Bay, dive, and enter the tunnel behind the colorful fish and old minecart. Dodge a shark attack, then turn right and ascend the ladder. An air current provides an oxygen pocket. Follow the current past two jellyfish to a ladder that leads to a dry tunnel.

A second treasure chest is located further along the path; players may bypass it if desired.

Assassinate the pirate at the tunnel corner, swim through the next tunnel, and wait for two pirates to eliminate each other. Remove remaining pirates, place a small red barrel against the east stone wall, and detonate it with a pistol from a safe distance.

Proceed through the tunnel to a large cave chamber, destroy walls to access the locked chest, and defeat the NPC carrying the key, which does not appear while the quest is active. Return to Great Inagua and open the chest at the docks to complete the quest.

The reward is a portrait of Blackbeard rather than gold. The quest location remains fixed, and the quest can be revisited after completion.