Sequence 3
Roadside Assistance
Escort Maria and Claudia to the Villa Auditore in Monteriggioni
Head up the road until you reach a human blockade.
Defend Your Family
To start things off, two guards will attack--one will go for you, the other after the girls. Evade their attacks and take them down with a few punches. Immediately after, the rest of the enemies will join in the fray. Luckily, since most will be pre-occupied with fighting another, murdering them is as easy as running up to each one and pressing attack. Once the final baddie falls, you'll complete the mission.
Casa Dolce Casa
Explore the Villa Auditore with Mario
Follow Mario through the city to his humble abode.
Visit the Blacksmith // Buy a Pair of Greaves and a Dagger
The blacksmith's not far--follow your map to find it. Once there, purchase the only two items he has: the leather Greaves and the dagger. The boots, as with all armor, will be equipped automatically. As for the dagger, you can switch to it, or any weapon, at any time by holding right right-trigger and selecting it.
Visit the Doctor
Now that you're equipped, head for the nearby Doctor--as marked on your map--and purchase five Medicines--you'll find it under "apothecary supplies."
Practice Makes Perfect
Learn How to Fight from Mario
Mario will walk you throw the basics of fighting, including using quick-steps to evade attacks, blocking, and countering--this last one is very important and a good skill to learn. When Mario challenges you to a battle, defend against his attack, then follow-up with a series of your own to defeat him.
Go to Mariol
Follow the map toward the marked area, in a bottom-floor room on the right.
What Goes Around
Follow Mario
Follow Mario up to the castle. Once they're, he'll give you some throwing knives, then head off to distract the guards. Equip the knives, then climb up the wall ahead, via the wagon and boxes, to the checkpoint.
Activate the Lever
After climbing up the wall, there are three nearby guards you should dispatch of with your knives. The first is on a rooftop dead-ahead--lock-on and press attack to send a knife his away. Now follow the walkway to the right to find another just ahead, then a third on the rooftops just beyond. Once clear, drop down and activate the lever by the gate to open it.
Kill the Guards
Just up the stairs wait several guards. Use your knives to pick off the first two--the rest will soon follow. Luckily, your band of men should take care of most of them, enabling you to simply use basic attacks or counters to clear out the rest.
Get to Santa Maria Assunta
With the guards cleared out, climb the stairs and speak to the injured guy by the fountain.
Go to Mario
Continue onward where you'll find Mario engaged in a large battle. Like before, simple attacks should be enough for the distracted guards, though use counters for those who target you specifically.
Find Vieri de' Pazzil
Head for the checkpoint on your rader--it's on a rooftop.
Assassinate Vieri de' Pazzi
You'll find Pazzi on top of the tower just across from you. Climb it and take him down. His henchmen will attack as well--just hold block and counter whenever one of them attacks first. Once they're out of the picture, Pazzi's a piece of cake--either counter, or attack after blocking to do him in.
A Change of Plans
Follow Mario // Read the Letter
Follow Mario until he gives you a letter you should read. After reading it, meet up with Mario in the room marked on your mini-map.
Reach the Villa's Viewpoint
Head for the building marked on your mini-map, then synchronize with the glowing viewpoint.
Collect the 4 Philosophical Codex Pages
There are four codex pages scattered around and outside the city's walls, all of which are marked on your map. Because some are so far away though, you'll have to rely on your full map instead of just your mini-map. The first two can be found nearby, on the east side of town. Another can be found to the west. Finally, the last one is located outside the castle, far to the east. Look for them all on the ground-level, in a corner, outside of the buildings.