There are many different trophies and achievements that you can unlock within Ghost of Tsushima, one of which is Monochrome Masters
Monochrome Masters requires players to Purchase an item from the Black and White Dye Merchants.
These merchants can be found easily enough and one of which can be found in the region of Izuhara and the other one can be found in the region of Toyotama
The merchants have a habit of selling Vanity Gear, Armor Dyes and Hats.
#1 MERCHANT (IZUHARA)
#2 MERCHANT (TOYOTAMA)
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