The Charm of Steadfast Fire is a New Game+ minor Melee charm in Ghost of Tsushima. The Way of the Flame lasts a lot longer. You get it by buying it from Baku the Voiceless in New Game+.
Start New Game+ and visit Baku the Voiceless on the island in the middle of Lake Izuhara, Ariake. He sells it for Ghost flowers alongside other New Game+ gear.
It is the natural partner for the Charm of Blazing Flame, also sold by Baku.
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.