The Symbol of the Guardian Brotherhood is a legendary crafting material used by Blacksmith Haedrig Eamon to craft the Guardian’s Jeopardy set. The Symbol of the Guardian Brotherhood drops from Dragus (demon trooper) in Act III: Stonefort.
The Symbol of the Guardian Brotherhood also drops from Busaw in Act III: Rakkis Crossing during the Crazy Climber event (Bring the spyglass to Lieutenant Gryffith) — which starts with Private James.
The Iron Wolves Doctrine is a legendary crafting material used by Blacksmith Haedrig Eamon to craft the Asheara’s Vestments set. It drops off Ssthrass (The Sliverbolt).
Ssthrass can be found in Act II: Dahlgur Oasis at the bridge leading to the entrance of the Ancient Waterway
Demon Hunters should double-camp Ssthrass because I got this recipe from him too: Sydyru Crust (Legendary 2-Hand Bow).
The Shard of Entsteig Plate is a legendary crafting material used by Blacksmith Haedrig Eamon to craft the Aughild’s Dominion set.
The Shard of Entsteig Plate is known to drop off Feklar’s Ghost in Act I: Festering Woods; and from The Archivist in Act II: Unknown Depths. Both elite Enraged Phantoms are rare spawns and might require you to create several normal difficulty games to find them. Both are also random Bounty targets in Adventure-mode.
The Shard of Entsteig Plate also drops from Lord Dunhyld (rare spawn) in Act I: Cemetery of the Forsaken – Bounty: Lady Dunhyld’s bones.
Note: Ascended items (white) are required to craft these set pieces. The Ascended items drop from about every place, but my favorite farming spot is Act V: Battlefield of Eternity which contains a lot of angel armor racks. Might take a few attempts in normal difficulty for the one you need to drop.
The Griswold’s Scribbling’s drops from about any bookshelf, and journal bag throughout all Acts, including the Angel Archives in the High Heavens. They have a decent chance to drop. I have 14 at the stash as I speak.
The location I have seen that have the most bookshelves is the Tristram Cathedral. The location with the most amount of journal bags is definitely Act V: Path of the Drowned (Bloodmarch) and Pandemonium Fortress Level 1-2. You can find them in normal-difficulty too.
Griswold’s Perfection – Sword
The Recipe: Griswold’s Perfection dropped for me at the Unknown Depths inside Act II: Archives of Zoltun Kulle. You enter the Unknown Depths through the left path of the Terminus.
The Tsunami Blade required to craft Griswold’s Perfection can be found in the weapon racks inside The Unknown Depths too.
The Eyes of the Dead is a legendary crafting material used to craft a 2-H weapon. The Eyes of the Dead is a random drop from Headcleaver in the campaign mode. He is the skeleton that spawns when Deckard Cain is under attack at Leoric’s Passage in the Tristram Cathedral. Set your game to start at The Legacy of Cain: Explore Cellar.
In Adventure-mode, there is a Bounty: Kill Merrium Skullthorn in Act I: Tristram Cathedral level 2. Spent about four hours on this one. Not recommended. On top of the random chance at looting Eyes of the Dead from him, there is the randomness of the bounty spawning him. The bounty won’t be available every time you create an adventure-mode map.
The Essence of the Twin Seas drops from a rare spawn Dune Thresher named Razormouth. He is also part of the Bounty: Kill Razormouth.
Take the Howling Plateau waypoint and follow the road north. Past the bridge is the Black Canyon Mines where you can find Razormouth usually beneath the sands. Look out for movement beneath the sand. The scales of his backbone can be seen. It drops in Normal difficulty too.
The Element of Celerity is a random drop from different rare elites. The most common one is an elite leaper rare spawn named Mange in Act I: The Weeping Hollow which is a bounty — Bounty: Kill Mange.
There is another bounty target in Act 1: Watch Tower Level 2. Talk to the NPC to start the Scavenged Scabbard event. You will find Armorer’s Bane in the hidden alley. It will appear as a yellow dot in the mini-map.
Fleeting Strap – Belt
The Element of Celerity is a required crafting material to craft the Fleeting Strap (belt).
The Demon Skin is a legendary crafting material found in Act IV: Gardens of Hope Level 2. Razorclaw and Haxxor has a random chance to drop this material. Khatun (Bounty: Kill Khatun) in Gardens of Hope Tier 1 has a chance to drop it too. They are rare elite Darksky Fire Demon.
The Demon Skin is used to craft the Demon’s Hide Set.
Thanks to d3ros_wiki
The Cultist’s Blood is a Legendary Crafting Material found in Act I. While there are a few sources it drops from, you want to farm the one that spawns permanently, not a random target, right?
Go to Halls of Agony Level 1 and kill Cultist Grand Inquisitor. He spawns every time you launch a game.
The Cultist’s Blood is used to craft a Legendary Dagger: Blood-Magic Edge. The Punyal required to craft this weapon can be farmed at the same location from the Torture Tools (weapon racks).
These are the level 70 Legendary Crafting Materials required to craft Legendary Sets and Legendary Weapons. Click on the name of the material to reach a page with more details on how and where to acquire them, as well as the recipe stats, NPC screenshot and the weapon 3D model.