Here is the full list of trophies you can unlock in Demon’s Souls for the PS3.
Adjudicator’s Trophy (Bronze) – Slayer of Demon “Adjucator”
Armor Spider’s Trophy (Bronze) – Slayer of Demon “Armor Spider”
Blood Master’s Trophy (Bronze) – Obtained Best Weapon by Suckerstone
Congratulant’s Trophy (Bronze) – Obtained Best Weapon by Faintstone
Darkmoon Master’s Trophy (Bronze) – Obtained Best Weapon by Darkmoonstone
Dirty Colossus’ Trophy (Bronze) – Slayer of Demon “Dirty Colossus”
Dragon God’s Trophy (Silver) – Slayer of Demon “Dragon God”
False King’s Trophy (Silver) – Slayer of Demon “False King”
Flame Master’s Trophy (Bronze) – Obtained Best Weapon by Dragonstone
Flamelurker’s Trophy (Bronze) – Slayer of Demon “Flamelurker”
Flying Dragon’s Trophy (Bronze) – Slayer of Demon “Flying Dragon”
Fool’s Idol’s Trophy (Bronze) – Slayer of Demon “Fool’s Idol”
Leechmonger’s Trophy (Bronze) – Slayer of Demon “Leechmonger”
Life Master’s Trophy (Bronze) – Obtained Best Weapon by Pulpstone
Maiden Astraea’s Trophy (Silver) – Slayer of Demon “Maiden Astraea”
Maneater’s Trophy (Bronze) – Slayer of Demon “Maneater”
Master Bowman’s Trophy (Bronze) – Obtained Best Bow by Spiderstone
Master Hitter’s Trophy (Bronze) – Obtained Best Weapon by Greystone
Master Slicer’s Trophy (Bronze) – Obtained Best Weapon by Bladestone
Moonlighter’s Trophy (Bronze) – Obtained Best Weapon by Moonlightstone
Old Hero’s Trophy (Bronze) – Slayer of Demon “Old Hero”
Old King’s Trophy (Bronze) – Conqueror of Old King Doran
Old Monk’s Trophy (Silver) – Slayer of Demon “Old Monk”
Penetrator’s Trophy (Bronze) – Slayer of Demon “Penetrator”
Phalanx’ Trophy (Bronze) – Slayer of Demon “Phalanx”
Poison Master’s Trophy (Bronze) – Obtained Best Weapon by Mercurystone
Rogue’s Trophy (Gold) – All Rings Obtained
Sage’s Trophy (Gold) – All Magic Learned
Saint’s Trophy (Gold) – All Miracles Learned
Shade Master’s Trophy (Bronze) – Obtained Best Weapon by Cloudstone
Soldier’s Trophy (Gold) – All Valuable Weapons Obtained
Storm King’s Trophy (Silver) – Slayer of Demon “Storm King”
Toughest Soul Trophy (Platinum) – All Trophies Obtained
Tower Knight’s Trophy (Bronze) – Slayer of Demon “Tower Knight”
Trophy of Distinction (Bronze) – Obtained Best Weapon by Clearstone
Trophy of Hardness (Bronze) – Obtained Best Weapon by Splinterstone
Trophy of Sharpness (Bronze) – Obtained Best Weapon by Sharpstone
World Uniter’s Trophy (Gold) – Old Beast Put to Sleep & World United