Assassin's Creed Revelations Walkthrough Part 29 – Forum of the Ox
Now the earlier hunt yields fruit. Head to the Forum of the Ox and go the sunken door that is marked.
Inside you trigger a cutscene. Where you learn the Templars have found the door that likely contains one of the Masyaf Keys. You hear them talking about how it took an earthquake to open the door. Ezio takes a shot at a barrel which hits one of the guards. They take off and you need to chase them.
Full Synchronization requires that you take No Damage.
*Falling in the water leads to immediate desynchronization*
You have 1 minute to catch up with the Templars.
Dash straight forward from the start. Hop the pillars then keep to the dock. After the bend, jump left onto the pillars coming out of the water. Cross the water and head to the right when you reach the wall, climbing it and heading into a short tunnel. Once you enter, the timer goes away.
Once you emerge, keep the stone arches between you and the Templars to ensure you will not take any damage at all. Long Jump when the Lantern comes up.
After the second cutscene, continue your dash forward, through the door way and up the wall. The only true point of concern is when you need to jump the stone pillars. Slow slightly here to assess a path straight across to the stone archway above then dash it. If you are less then certain, slow it a little more.
After you climb up, long jump across, go through the arches then head left. After the cutscene with the crumbling walkway be sure to long jump off the lantern as the alternate route you are taken to is very likely to get you shot or drop into the water. Either way, head forward. The next point of concern comes when you see the Templars start throwing Gunpowder barrels at you. This is another case of slowing some to clear this part without falling into the water. More free-running is on the list. You will eventually reach a Zipline that takes you over the Templar boat. When it does, you will get the prompt to Assassinate the Templar. Hit the Primary Action to do so. This end the chase part of the Forum of the Ox and take it onto the second part.
Here you need to face down the surviving Templars. If you have not taken any damage, this is the last concern before the completion of the memory. Either you can engage using Sword Counter-Kills or Smoke Bombs. Either way makes it simple to avoid taking damage and ensure Full Synch.
Once you are done, collect the nearby chest. They have a lot of money and numerous ingredients inside. Once you have, switch on Eagle Sense and look at the middle door. It will be revealed as the proper one. After that, as usual, go inside and collect the key.