From Ofiers Distant Shores - Novigrad (Hearts of Stone)

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Area: Novigrad
Location: Upper Mill
Quest Giver: Merchant
Other Requirements: Hearts of Stone DLC

This quest can be started one of two ways, the first is by speaking with the merchant at Upper Mill (pictured above) and the second way is by finding one of the Oferi Diagrams, like during the Rose on a Red Field Quest.