Assassin's Creed 4: Black Flag Walkthrough Part 47 – Templar Hunt: Opia Apito “Right-Hand Man” & “The Trail of Lucia Marquez”
Right-Hand Man
Opia is very close to where the last mission ended. Follow her to start off the next mission. Follow her over to the hut. She will then tell Edward to hide. Duck into the nearby pile of palm leaves. This makes for a useful location.
When Opia knocks on the door then Vargas will go running out of the house from the back. Give chase and follow Vargas for now. He will run through the settlement out to the docks and onto his ship which is departing. You will see a cutscene then be prompted to head back to your own ship.
Mark Vargas' ship with a marker and set off after him. When he is in range, hit him with a mortar volley or whatever attack is available. Board his ship. As the ship is reeled in, try to use the swivel cannon to take down Vargas. This will expedite things greatly. Otherwise just get over there and deal with it like any other capture: Kill Vargas.
The Trail of Lucia Marquez
Head to the Pinos Island to the North of the Caymans This is where the final mission will take place. Talk with Opia to begin the mission. After that you are trailing a man to see if he will lead them to their target.
Move forward and into the second or third Stalking Zone in front of you. Use Eagle Vision to mark your target and make your life a lot easier. Move up to the final Stalking Zone on the beach as he goes around the horizontal tree near the top of the beach. There is a clear trail of Stalking Zones leading you deeper into the island. Follow them to keep up with your target. Just remember to use Eagle Vision to quickly see where the next one is. He will lead you to an entrance of a temple. Climb up the wall just to the right of the entryway he uses. Time to deal with some Soldiers.
When it comes to the first group of soldiers there are a few options. You can use a few Berserk Darts and let them battle it out with you picking off the survivors. There is also a Powder Reserve that you can hit with a careful shot. Pick off the survivors.
This will draw out more of the Soldiers and Officers stationed here. If you want to make quick work and ensure your ally survives, then equip the Smoke Bombs. As the enemies draw in toward Opia then drop one at their feet. Just slaughter your way on through after that.
Lucia will reveal herself at this point. Just chase on after her. She will duck into a Stalking Zone and wait for you. The best thing you can do is approach swiftly and kill her before she can shoot you. It is very easy to catch her even after the shot is fired. This will net you another Templar Key.