Here is the full list of all 38 Demon's Souls (EU) trophies - there are 27 bronze, 5 silver, 5 gold and 1 platinum.
All Trophies Obtained
All Unique Weapons Obtained
All Spells Learned
Obtained Best Weapon by Darkmoonstone
Old One Put to Sleep & World United
All Rings Obtained
Slayer of Demon “False King”
Conqueror of Old King Doran
Slayer of Demon “Blue Flying Dragon”
All Miracles Learned
Obtained Best Weapon by Mercurystone
Obtained Best Weapon by Marrowstone
Slayer of Demon “Maiden Astraea”
Slayer of Demon “Dirty Colossus”
Obtained Best Weapon by Faintstone
Slayer of Demon “Leechmonger”
Obtained Best Weapon by Greystone
Obtained Best Weapon by Bladestone
Obtained Best Weapon by Suckerstone
Slayer of Demon “Penetrator”
Obtained Best Weapon by Cloudstone
Obtained Best Weapon by Clearstone
Slayer of Demon “Dragon God”
Slayer of Demon “Storm King”
Slayer of Demon “Old Hero”
Obtained Best Bow by Spiderstone
Obtained Best Weapon by Dragonstone
Obtained Best Weapon by Sharpstone
Obtained Best Weapon by Hardstone
Slayer of Demon “Adjudicator”
Obtained Best Weapon by Moonlightstone
Slayer of Demon “Old Monk”
Slayer of Demon “Maneater”
Slayer of Demon “Fool's Idol”
Slayer of Demon “Flamelurker”
Slayer of Demon “Armor Spider”
Slayer of Demon “Tower Knight”
Slayer of Demon “Phalanx”