There are 51 Trophies that can be collected.

Bronze

Bone Collector
Defeat the witch Straeggele

Ice Breaker
Defeat the witch Trude

Fire Fighter
Defeat the witch Holda

Until Next Time…
Force Faust to retreat

Storm Stopper
Defeat the witch Trendula

Hair Cutter
Defeat the witch Rapunzel

Stone Crusher
Defeat the witch Verderinde

To the Fires of Hell
Defeat Faust

Novice Executioner
Beat the game on Page

Average Executioner
Beat the game on Squire

Skilled Executioner
Beat the game on Knight

Terror
Acquire the Scythe of the Assassin Queen

Fright
Acquire the Scythe of Imperial Massacre

Soul Grabber
Collect 10,000 souls

Combo Master
Attain the highest possible combo rating

The Sonic Knight
Perform a 30-hit combo

Take One for the Team
Perform 10 counterattacks while taking enemy attacks

Ring Around the Rosie
Catch and defeat five enemies at once with Mag Mell's Rose

Keeping Healthy
Collect 100 Recovery Items

A Worthy Apprentice
Defeat 50 enemies with the help of Minukelsus

Growing Power
Upgrade a Witchcraft

Witchcraft Collector
Acquire all Witchcraft

The Finer Things
Acquire all equipment

Light Reading
Acquire a collection item

Blood Spilled
Defeat an enemy

Blood Bath
Defeat 100 enemies

Executed
Land a Finisher

Skillfully Executed
Land 100 Finishers

Head Bangin'
Bash the same enemy into a wall five times

Get 'Em Up
Pick up the same enemy five times

Nice Try!
Repel an enemy's attack 10 times

'Tis But a Scratch!
Experience your first revival

It's Just a Flesh Wound!
Revive 50 times

Bodyguard
Save Gretchen from enemy attack

Guardian Knight
Save Gretchen from enemy attack 50 times

Eye Candy
Use Witch's Embrace when no enemies are present

I'm Taking You With Me
Damage both yourself and an enemy with Witchcraft

Careful With That!
Damage both yourself and an enemy with Witchcraft 10 times

Touch Too Much
Carry Gretchen around for a long time

Silver

Master Executioner
Beat the game on Hexen Knight

Soul Reaper
Collect 100,000 souls

Souls United
Defeat 200 enemies with Knight's Fury

Her True Strength
Defeat 200 enemies with Witch's Embrace

Information Junkie
Acquire all collection items

Bloody Massacre
Defeat 1,000 enemies

Expertly Executed
Land 1,000 Finishers

Elegantly Executed
Land 100 Perfect Finishers

Gold

Legendary Executioner
Beat the game on Witchslayer

The Witch's Ultimate Weapon
Acquire Spirit Cannon

Platinum

Supreme Witchslayer
Fully execute your Knights Contract

1 Secret

http://www.ps3trophies.org/game/knights-contract/trophies/