Assassin's Creed 4: Black Flag Walkthrough Part 27 – Sequence 5: “The Forts”
Optional Objectives:
Use the Mortar to damage the fort
Use a running Assassination to kill the Officer
Make for Nassau when you are ready to continue with the story missions. When you get there you will have a new target, a Fort. Accept the mission by Fast Traveling directly to it or to Nassau then making to the tavern. Edward encounters both Calico Jack and Charles Vane. Time for some looting of a higher caliber. Set out for the Jackdaw and Fast Travel to the closest place you can manage to the mission start.
When it comes to dealing with this, you need to use the mortars to have the best chance of making it in and through. Sail in close so you are in range for the mortars then start alternating between the mortars and your cannons to maximize the damage you are inflicting. One of the best things you can do though, is quick sail in, fire off a mortar barrage then start luring the Brig that will be pursuing you away from the fort. This will make it a lot easier to just deal with the fort. This will satisfy one of the optional objectives and make your life a bit easier.
The brig is a fair opponent, even with an Upgraded Jackdaw. Still with distance from the Fort, it will be a good ship on ship battle. This can be started without much trouble. Just remember to brace when taking fire.
When you are focusing on the fort, there are a few things to keep in mind. Always be moving. This makes it harder for the Mortar to land a direct hit on you and it gives you a number of better angles. After you land some good hits on the fort defenses then you will see Swivel shot points you can fire on. Do so immediately to inflict major damage. Finally, sweep in front of the fort and unleash broadsides. While Heavyshot is tempting, it does not get the height you need to actually do damage. When the forts 2 cannons are down, you will be prompted to head on in toward the fort itself.
Head to the marker by the Fort and dock. When the Jackdaw is docked, start on in toward the fort itself. Head on up the ramp until you find the collapsed and burning gate. Climb up to the right of that and you are onto the attack on the fort.
Enter the first area. You have your crew fighting the Soldiers and Officers within. Take them on down if you want but otherwise just run on through. Run to the North and up the sloped roof. Head on through the doorway in front of you. You will see the Captain of this Fort and he will start running toward Edward. Charge him and kill him with a Running Assassination. This will stop all other hostile activity and give you a nice respite. Now you need to make it to the War Room.
Head to the South and then turn to the right and use the lift to quickly get up to the higher level. Head for the marker after that and open the doors there. Edward will find Governor Torres there waiting for the Slaver who claims to have found the Sage. Edward hatches a scheme to take down this Slaver.