Tadayori's Armor is the archer's set from the Mythic Tale The Legend of Tadayori, once worn by the legendary bowman Tadayori Nagao. It speeds up nocking and reloading and stretches Concentration, so it is the one to wear if you fight with bows.
Start The Legend of Tadayori in Azamo, Izuhara, and follow it to the cliff overlooking Azamo Bay, where the armor waits.
Noble Talon is the default. Autumn Victory, Relentless Hawk and Summer Ocean sell at Izuhara merchants and Hunter at Dusk at the Black Dye Merchant. Flowers of War and Archery Master's Attire are New Game+ dyes at Baku for 15 Ghost flowers.
Aaruul
Aaruul is one of the 50 Mongol Artifacts, pieces of the invaders' culture and warfare you can study. It sits at a camp south of Izuhara Clearing in Izuhara, and finding 20 artifacts counts toward the Know Your Enemy trophy.
Adachi Dragon Mask
Adachi Dragon Mask is a New Game+ mask sold by Baku the Voiceless for 5 Ghost flowers. It does not exist in a first playthrough.
Adak Tree
Adak Tree is one of the 50 Mongol Artifacts, pieces of the invaders' culture and warfare you can study. It sits at Yoichi's Crossroads in Izuhara, and finding 20 artifacts counts toward the Know Your Enemy trophy.
Adventurer's Fortune
Adventurer's Fortune is a dye for Traveler's Attire. It costs 10 flowers at the Izuhara merchants. Like every dye it only changes colours.