Ac 2 v 42 - Dead On Arrival
0Unlocked After: Sequence 6 - Memory 2: Romagna Holiday
The target is somewhere within the green circle on the map. Unless his location is completely random, he should be on the rooftops somewhere. Climb onto a building and use Eagle Vision to locate the agent. He's a runner, so try to take him out swiftly. Maybe hit him with a couple of Throwing Knives. If he does manage to take off, he's not very fast, so you shouldn't have much difficulty catching up and ending him with your Hidden Blade.
Go Towards the Light
Unlocked After: Sequence 6 - Memory 2: Romagna Holiday
Your target is atop the lighthouse along the north coast of Romagna. Exit Forli and make your way to the red target on the map. The lighthouse is a restricted area, so the guards are on high-alert and will attack on sight. To avoid getting into a fight, run around to the north side of the warehouse and climb up onto the broken archway. Assassinate the archer from the ledge using the Hidden Blade and then take out the Brute there.
Get on top of the wooden posts left of the door and then begin climbing the lighthouse. Climb all the way up to the top of the lighthouse to reach the target. Get onto the ledge and perform an Air Assassination with your Hidden Blade to kill the target and complete the memory. - https://www.supercheats.com/guides/assassins-creed-ii/