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Dark Souls 3: Greirat of the Undead Settlement
A useful vendor who sells a number of goods not available elsewhere, Greirat of the Undead Settlement is the first NPC most players will encounter outside Firelink Shrine – provided they explore thoroughly. To recruit Greirat, search High Wall of Lothric for the Cell Key and release him from his prison, and agree to deliver a ring for him.
Advance his storyline by finding Loretta’s Bone in Undead Settlement. Return this key item to the thief. The next time you return to Firelink Shrine Greirat will be temporarily unavailable as a vendor, but speaking to him with net you the Curl Up emote.
Some time later Greirat will be back to his cheerful self, and will offer to go out pillaging. Agree to this request and he’ll be sent from the Shrine – but will return with new items to sell. Sending Greirat on this journey may be a factor in the later appearance of Unbreakable Patches.
The second time Greirat goes out to pillage there’s a chance he may be killed, and his body left near the Church of Yorshka bonfire in Irithyll of the Boreal Valley. The exact conditions of his death are not yet known, but seem to be related to Patches and Siegward of Catarina. To keep Greirat alive during his second journey, complete Siegward’s questline up to his adventures in Irithyll of the Boreal Valley and do not speak to Patches while Greirat is away. Greirat will return after you defeat Pontiff Sulyvahn.
Greirat can make a third scavenging trip, but at this stage it seems he will always die in the process. His body can be found on a rooftop in the Grand Archives in Lothric Castle.
If Greirat is killed, you can loot Greirat’s Ashes from his body. Deliver this key item to the Shrine Handmaid and she will offer Greirat’s inventory for sale.