There are 36 Trophies that can be earned in this title.

Bronze

Swamp Sweet Swamp
Use the magic mirror

Ogres Rock!
Win the training fight in the Forest

Swamp Sweep
Defeat the witches in the Swamp

Towers Are For Sissies
Defeat the Fairy Godmother in Dragon's Keep

Back to the Grave
Beat the Skeleton battle in the Peasant Village

Ring Them Bells
Find and return all three bells in Peasant Village

Big Treasure
Open a big treasure chest

Let's Start a Sing-a-Long!
Use Donkey Radio on an enemy

Green And Mean
Scare an enemy as Shrek

Ogre Horn
Sound-blast an enemy with Fiona

Too Cute
Use Puss in Boots' 'big eyes' to charm an enemy

Just Getting Started
Get your first health upgrade

Silver

Shrek Goes Green
Fill half of the Ogre Power meter

Paid the Piper
Defeat the Pied Piper in the Catacombs

Sinking Ship
Sink the pirate ship

Swamp Complete
Complete 100% of the Swamp

Dragon's Keep Complete
Complete 100% of the Dragon's Keep

Peasant Village Complete
Complete 100% of the Peasant Village

Catacombs Complete
Complete 100% of the Catacombs

Docks Complete
Complete 100% of the Docks

Rumpel's Palace Complete
Complete 100% of Rumpelstiltskin's Palace

Ogre Camp Complete
Complete 100% of Ogre Camp

Shopping Spree
Purcahse all store items

Team Shrek
Defeat an enemy with each of the four characters in 1 battle

Fear My Roar
As Shrek, scare five enemies at once

Queen of the Swamp
As Fiona, sound-blast five enemies at once

Purr…
As Puss, enchant five enemies at once

Where's the Party?
Use Donkey Radio on five enemies at once

Ogre Outpost
Complete the Cooperative Multiplayer mode puzzle in the Swamp

Ogre Outlaws
Complete the Cooperative Multiplayer mode puzzle in the Docks

Ogre Mayhem
Complete the Cooperative Multiplayer mode puzzle in the Peasant Village

Let's Have Some Fun
Defeat an enemy in the Cooperative Mutliplayer mode

The Party's Here
Complete a battle while in the Cooperative Multiplayer mode

Gold

100% Green Ogre
Fill up the Ogre Power meter

The Royal Highness is Heinous
Rumpel Defeated

Platinum

True Love's Kiss
Unlock all other trophies

http://www.ps3trophies.org/game/shrek-forever-after/trophies/