Eagle Strike: Climbing the Ranks
Recall that an eagle strike assassination is a jump followed by a catch ledge and air assassination. We have yet to find a target in AC2 that can be eagle struck where he stands (like William de Montferrat in AC1). However, there are some targets who will follow Ezio and allow themselves to be set up for a sweet eagle strike. Savonarola's lieutenant in Climbing the Ranks is one example and he happens to be near the highest view point in the game, Giotto's Campanile in Florence.
The first step is to follow the target up to the highest roof. He won't follow you until you engage him in combat. It's not necessary to actually draw a weapon. Just get close enough to him that a blue arrow appears over his head.
Now turn around and run toward the Duomo. Be careful to maintain a distance of 50 meters or less between yourself and the target. Otherwise it's total desynchronization. It's up to you if you want to thin out the entourage by fighting some guards. In the video I don't kill anyone prior to the assassination. I do some stalling tactics to preserve health while waiting for the target to catch up.
Run up the alley between Basilica di Santa Maria del Fiore and Giotto's Campanile. When you see a tree on your left, climb the Basilica just before passing it. Slip over the edge to become Unseen. Note that most of the regular guards leave when you Vanish. Only the main target and sometimes one or two bodyguards stay behind.
Climb the Campanile as shown. Again, maintain a distance of less than 50 meters. It's too bad we can't do an Eagle Strike from the very top of the tower. 
Straddle the hexagonal corner for the proper jump angle. It doesn't matter where Ezio's body is as long as he has one hand on either side of the corner.
Once in position, it's a standard eagle strike: Select the Hidden Blade. Jump straight backwards (Right Trigger + Feet). Wait until you fall next to the stained glass window. Catch ledge left (Left Thumbstick left + Unarmed Hand). Air assassination (Armed Hand).
great eagle strike stab. I was about to ask if its possible from any higher up but then realised that maintaining a short distance to target plays a factor. it would look amazing from the top but never mind.
Good job. I'll be trying it out for definite 
AC2 measures distances in three dimensions. That's a good thing when you're trying to find a treasure chest or something on your map. The distance meter on your mini-map will give you an idea of how far above/below you the item is and whether you're getting warmer or colder as you go up and down. AC1 only accounts for horizontal distances.
I believe the requirement on Climbing the Ranks is less than 50 meters. At the time of this Eagle Strike, my distance meter said 39. It's possible that you can push that another 10 meters and I invite you to try. You will get a warning at 40 meters.
This tower is much taller than 50m, so an eagle strike from the top will only be possible if we can manage to get target into position with no distance requirement. For example, an unaware target might be lured in with dead bodies.
Although I don't think anything will ever beat Ian's Eagle's Strike vid on William in AC1, this came pretty damn close. Excellent job, stab.
It's gorgeous, stabguy. You make it look easy! Moving like the wind!
For those who aren't aware - it isnt apparent from the video that the design of an eagle strike assassination is quite a challenge. What's especially impressive is that stabguy manages to use 2 of the most famous structures in the game to perform the eagle strike! Congrats stab! This was really well done.