Black Bart's Gambit

First sail over to Black Bart. After talking to him sail forward to locate a Portuguese ship. There are a ton not too far from you. Once you get close to one you need to steal it is flag. Hop off your ship and sneak onto the other one. Climb up the robes to get to the masts. Once up there take the flag and jump back into the water. Get on your ship and continue foreward until you get by some land There is a man with a chest on the bench. so that is something you want. Go swim ovet to the land and snake your way forward until you get to the chest. Loot it then get back to your boat. Tail the ship in front of you now making sure to not cause detection from the other ships. Swing wide right in the clearing to avoid the ships and outcroppings. You will come up to another beach here. There are two guard tower however you see fit. Move on to the second tower now The easiest way to take on this other tower is to simply climb up it. Once up here and the guards are taken care of swing on the rope from the tower to the big ship you have been trailing. Try to keep the ships captain with an aerial takedown while swinging across the gap. Once the captain is dead you take control of the ship. Make a run for it while still taking out the enemy ships. This boat is pretty powerful so the enemy ships should go down quickly. Once your path is clear you should be good!