Below are the objectives for The Legend of Black Hand Riku tale in Ghost of Tsushima.
Listen to Kashira’s tale in Fune’s Refuge
Head to the campfire in Fune’s Refuge and speak with Kashira.
Leave Fune’s Refuge
Do as it says and leave!
Search Mount Takenotsuji for Minato
Travel to Mount Takenotsuji, which is north of Tatsu’s Ladder and east of Fort Sakai.
Rescue Minato
Defeat all the enemies surrounding Minato then release her.
Rest at Minato’s campfire until nightfall
Interact with her campfire.
Find the glowing water on the northeastern coast
Travel northeast near Barrier Cove.
Follow the glowing water on the northeastern coast
Follow the water north past the Thunderhead Cliffs to reach the Mysterious Cave.
Investigate the cave
Head into the cave and enter the passage by shooting the brazier to the right of the door with a flaming arrow. Next, use your grappling hook to break down the barrier.
Search the cave for the Sarugami Armor
Head through the cave lighting the braziers as you see them. Eventually you’ll stumble across Black Hand Riku and a duel will initiate. Defeat him in battle.
Take the Sarugami Armor from Riku
Take the Sarugami Armor and Sarugami Helmet from the Blank Hand Riku.
Escape Riku’s lair
Just past the dueling area, there will be a path leading out.
Defeat Kashira and his men
Defeat the enemies. You’ll then receive the Charm of Versatile Skills which doubles the effect of Minor Charms, if it is the only Minor Charm of the same category equipped and Raider Captain’s Headband.