This is beyond ridiculous. Many of them depend on rare drops from an enemy that only appears twice in the game. Also, three required weapons require the same boss soul. So, at a minimum, you'll be playing 2.5 playthroughs...though the rare drops will probably make it many more than that:
Ghost Blade:
New Londo Ruins. Dropped by female ghosts.
Priscilla's Dagger:
Painted world of Ariamis. You must cut off the tail of Priscilla the crossbread, boss of Painted World to get this weapon.
Silver Knight Straight Sword:
Anor Londo. Dropped by Silver knights.
Drake Sword:
Undead Burg. Shoot the tail off of the Red Drake guarding the bridge.
Stone Greatsword:
Darkroot Garden. Dropped by the great stone knights before the butterfly boss fight.
Greatsword of Artorias:
You must Ascend a +10 weapon with the soul of Sif, The Great Gray Wolf.
True Greatsword of Artorias:
You must ascend a +10 Broken sword dropped by the sword weilding zombies of Undead Burg/Parish and the soul of Sif, The Great Gray Wolf.
Great lord Greatsword:
You must ascend a +10 weapon and the soul of Gwyn, The Lord of Cinder.
Moonlight Greatsword:
You must cut off the tail of Seath The Scaleless in Crystal Cave.
Black knight Sword:
Random drop from any Sword Weilding Black Knight in the game. These enemies don't respwan, so make sure your item drop rate is high. Try equipping the Gold serpant ring before fighting them and pray.
Dragon Greatsword:
Cut the tail off of the Ancient Dragon at the end of Ash Lake. Supposedly, you can cut off the tail, and still enter a covenant with the dragon, but I haven't tried yet.
Black knight Greatsword:
Random drop from any Sword Weilding Black Knight in the game. These enemies don't respwan, so make sure your item drop rate is high. Try equipping the Gold serpant ring before fighting them and pray.
Jagged Ghost Blade:
New Londo Ruins. Dropped by male ghosts.
Quelaag's Furysword:
You must ascend a +10 weapon using the soul of Quelaag, the boss to ring the second bell. A good weapon to use would be a Scimtar purchased pretty cheap from the Undead merchant in Undead Burg.
Gravelord Sword:
This is a reward for joing Gravelord Nito's covenant.
Chaos Blade:
You must ascend a +10 weapon and the soul of Quelaag. A good choice is the Iaito found in Blighttown.
Velka's Rapier:
This weapon can be found on a corpse in the Painted World of Ariamis.
Golem Axe:
Make a +10 axe and use the core of the Iron Golem to ascend this weapon.
Black Knight Greataxe:
Dropped by axe weilding black knights. There are only 2 of these guys in the game. One in the catacombs and the other is in the very last area of the game. Good luck getting it.
Dragonking Greataxe:
The Depths. Cut off the Gaping Dragons tail to get this weapon. He is the boss of The Depths and the means of getting the key to Blighttown.
Grant:
Dropped by NPC invader "Divine Knight Leeroy" He will invade you randomly in The Tomb of Giants. You must be unhollowed to be invaded by him.
Dragon Tooth:
Anor Londo. Found in a treasure chest.
Smough's Hammer:
Must ascend a +10 club/mace and the soul of Smough, one of the bosses of Anor Londo to get this weapon.
Silver Knight Spear:
Anor Londo. Dropped by Spear-type Silver knights.
Moonlight Butterfly Horn:
Ascend any +10 Spear and the soul of the Moonlight Butterfly for this weapon.
Dragonslayer Spear:
Ascend any +10 rapier type weapon and the soul of Ornstein, one of the bosses of Anor Londo for this weapon.
Titanite Catch Pole:
Dropped by the Prowling Demons. The ones with the lighting staff near the blacksmith on the way to Darkwood and one down in Sen's Fortress.
Black Knight Halberd:
Dropped by spear weilding black knights. There are only 2 of these guys in the game. One in darkwood basin, guarding the grass crest shield and the other is in the very last area of the game. Good luck getting it.
Lifehunt Scythe:
Ascend any +10 Halberd/scythe and the soul of Priscilla, the Half Breed to get this weapon.
Dragonbone Fist:
Ascend any +10 Cestus or claw and the core of the Iron Golem fot this weapon.
Dragonslayer Greatbow:
Anor Londo. Found in a treasure chest.
Darkmoon Bow:
Ascend any +10 Bow and the soul of Gwyndolin, the Darkmoon God to get this weapon.
Tin Darkmoon Catylist:
Ascend any +10 catylist and the soul of Gwyndolin, The Dakrmoon God to get this weapon.
Crystal Ring Shield:
Ascend a +10 shield/buckler and the soul of the Moonlight Butterfly to get this shield.
Crest Shield:
Undead Asylum (revisited) You will be attacked by the soldier who gave you the estus flask the first time you were here. He drops this shield.
Dragon Crest Shield:
Found on a corpse next to the sword of Astoria in Valley of Drakes.
Silver Knight Shield:
Anor Londo. Dropped by any silver knight type.
Black Knight Shield:
Dropped by any Black Knight type you come across.
Stone Greatshield:
Darkroot Garden. Dropped by any Stone Knight laying around before the boss fight area with the Moonlight Butterfly.
Havel's Greatshield:
Anor Londo. Found in a treasure chest.
Greatshield of Artorias:
You must ascend pretty much any +10 shield/buckler and the soul of Sif, The Great Grey Wolf to aquire this shield. Damn, you need Sif's souls for 3 things!!
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