Here is the full list of all 29 Hitman: Contracts HD trophies - there are 12 bronze, 10 silver, 6 gold and 1 platinum.
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All Firearms collected and displayed in the training room
All Machine Guns collected and displayed in the training room
All Sniper Rifles collected and displayed in the training room
All Heavy Weapons collected and displayed in the training room
A mission has been completed with precisely 47 kills
All Hand Guns collected and displayed in the training room
You have found all Melee Weapons
All Shotguns collected and displayed in the training room
All Assault Rifles collected and displayed in the training room
You picked up the Gold Desert Eagle Dual
You picked up the Minigun
Completed normal difficulty
Completed expert difficulty
Completed professional difficulty
You drowned someone
You retrieved the SPAS-12 from the florist
You killed the ghost
You used explosives on a victim
You poisoned a victim
5 Silent Assassin ratings awarded on the Normal difficulty
5 Silent Assassin ratings awarded on the Expert difficulty
5 Silent Assassin ratings awarded on the Professional difficulty
A Silent Assassin rating has been awarded
A successful headshot has been performed
You completed the first mission on any level
You knocked a victim out
An innocent person has been killed
A successful kill has been performed