Assassin's Creed 2 - Sequence 3 - What Goes Around [1]

Follow Mario and his mercenaries up to the city walls. Climb the wall while they distract the guards at the gate. Select your new throwing knives by going into the inventory wheel with Q. There are three archers on the rooftops near the gate. Lock onto each of them and throw a knife at them to take them out. Once that's done, interact with the lever near the gate. Head out there and help out Mario and the mercenaries by slaying each of the guards. Head inside together. With a group of the mercenaries, guide them toward the guards like you did with the Courtesans. Target them and hit Triangle to send the mercenaries into battle. Start dueling it out with each of the guards. Remember that attacking ones with their backs to you is an instant kill. Counter and attack the rest to defeat them. You can fight more but you don't have to. You can just walk past the next few guards if you prefer until you get to the marker. Speak to the injured man to get a new destination. Head there to find Mario under attack. Lock onto any guard and send your mercenaries into action by hitting Triangle. Mario will eventually tell you to move on and find Vieri while they deal with the guards. Do so and abandon this fight for now. You might have gained Notorious status again. Find some posters or assassinate an official along the way if you can. Remember that when climbing, your mercenaries can't follow you so tell them to wait. Once you're ready, move toward the yellow marker. You won't need the mercenaries since you need to climb a roof to get to it. Go to the site of the next big fight and help out Mario by defeating the guards. You'll likely become Notorious yet again if you shed it earlier. Climb the wall when you're ready and then up to the guard tower where Vieri is. He'll spot you no matter what, so no stealth kill this time, my friend. Duel with him and his guards. Use countering as much as possible. More guards will climb up to help Vieri so try to focus on him when you can. He can counter you too, but not very often. Weaken him enough and deliver the final blow to end his tale.