Here is the full list of all 51 Assassin's Creed II trophies - there are 34 bronze, 15 silver, 1 gold and 1 platinum.
Unlock all trophies.
Sweep 5 guards at once by using a Long Weapon.
Wear the Auditore cape in each city.
Collect all the Feathers.
Unlock all 20 pieces of Subject 16's video.
Perform an Air Assassination on a Poisoned NPC.
Stun 4 guards at once by throwing sand in their face.
Hide 5 dead bodies in a Bale of Hay.
Spend 5000 florins on Courtesans.
Tint your clothes with those colors: Wetland Ebony and Wetland Ivory.
Escape the hideout.
Complete DNA Sequence 14.
Find the 8 statuettes in Monteriggioni.
Complete DNA Sequence 11.
Complete DNA Sequence 10.
Get all Hidden Blades, Item Pouches and Armor upgrades for Ezio.
Complete DNA Sequence 9.
Discover the Assassin's Tomb inside Santa Maria della Visitazione.
Discover the Assassin's Tomb inside the Basilica di San Marco.
Complete DNA Sequence 8.
Kick a Guard while using the Flying Machine.
Complete DNA Sequence 7.
Buy a Painting from Florence and Venice.
Discover the Assassin's Tomb inside Santa Maria del Fiore (The Duomo).
Toss more than 300 florins on the ground.
Reach 80% of your stronghold's total value.
Complete training and reenter the Animus.
Complete DNA Sequence 6.
Discover the Assassin's Tomb inside the Rocca di Ravaldino fortress.
Complete DNA Sequence 5.
Intercept a Borgia Courrier.
Kill 10 enemies while remaining in conflict without being hit.
Discover the Assassin's Tomb inside the Torre Grossa.
Complete your first assassination mission for Lorenzo Il Magnifico.
Complete DNA Sequence 4.
Discover the Assassin's Tomb inside the catacombs under Santa Maria Novella.
Pickpocket 1000 Florins.
Upgrade a building in the Stronghold.
Complete DNA Sequence 3.
Complete DNA Sequence 2.
Synchronize 10 View Points.
Unlock a piece of Subject 16's video.
Use your Eagle Vision to scan a Glyph in the environment.
Complete DNA Sequence 1.
Defend a woman's honor.
Win a race against thieves!
Perform a Leap of Faith from the Top of Florence's Giotto's Campanile.
Sprint for 100 meters.
Enter the Animus 2.0.
Break out of Abstergo.
Be reborn as Ezio Auditore Da Firenze.