Assassin's Creed 4: Black Flag Walkthrough Part 32 – Sequence 6: “Devil's Advocate”
Optional Objectives:
Rescue 5 Survivors
Kill 3 guards stunned with Smoke Bombs
Fast Travel over to Salt Lagoon then approach the ship at the marker and hit the prompted button to begin the mission. This will put you on a course to collect a number of survives and catch up to Blackbeard to learn more of what he is doing.
Sail straight on in to the mist. Your only guide for now is the marker ahead of you showing the location of the Queen Ann's Revenge. You need to make your way on through the rocks and tight areas using your eyes and your minimap. While doing this you need to listen to Adewale. He will point out when he sees a wreck. You will want to head toward those. You will find both cargo (for lotting) and Survivors (for the Optional Objective). On through and carefully. You will find Survivors without too much effort. The hard part would be tracking down a ship and sinking it. This can be done if you want to hurry along the optional objective. Be careful if you take this path. You will have a number of chances just remember to sink the ship instead of boarding it and to only engage one or two at a time. It is not hard to wind up fighting three plus without meaning to.
After a while you will make it into the search area. Once there head for Mariguana Island. It is found in the Southern part of the Search area. Just get close. When you do, let go of the wheel and make the straightest path you can toward the Queen Anne's Revenge. You will see a fight is happening on land.
Rush into the battle. You want to equip your swords and some Smoke Bombs. Rush into the thick of the fight. Quickly drop a Smoke Bomb. This will stun all the nearby Soldiers, Officers and Brutes. Quickly dispatch whoever is effected that you can. This will not only push you toward the optional objective, but make the fight easier. When this fight is done, head for the Queen Anne's Revenge and take her wheel. Back on the sea you have a naval battle you need to make it on through.
The Queen Anne's Revenge is a very powerful ship. She fires 3 barrages during a broadside. While this means more damage, it also means you need to keep the target in range longer to land that massive damage. Most else carries over from the Jackdaw..
Takng on the Galleon is something else to the previous experiences. You need to quickly adapt to the ship and take down the Man o wart.. Listen to Blackbeard and bear down on the ship fast. You need to get in the first blows. Use Heavy Shot over a broadside whenever possible. Just keep close but be sure to brace whenever there is fire incoming. The biggest loss you will suffer is that of the mortar. It can take a few tries but you can take the Man O War.
When you do disable her, move in close to trigger a cutscene. Edward is sent after the Captain He automatically uses a lift to quickly get up high. When you have control again, jump forward onto the mast in front of you. Take that on over to the man o war. Target the far Gunner to stop him from shooting you. The closer one you can avoid by going close to the central mast. From there, head over to the far side of the beam you are on. You should be able to spot the captain without much trouble. Now you can perform an aerial assassination on him or simply shoot him. The choice is yours. When he is dead, the memory will end and you are onto the next part of the sequence.
If you have things to find in Nassau, this is the time to do. It will get much harder very soon.