Quest name:
Inazuma Hidden Quest- The End of Iwakura Clan
Quest Rewards:
5 Precious Chests, 1 Luxurious Chest, Achievement "Iwakura Out"
Requirements:
Adventure Rank above 30. Complete "The Immovable God and the Eternal Euthymia" and "Sacred Sakura Cleansing Ritual" quest series to obtain the "Memento Lens". Unlock all Statues of The Seven on Narukami Island, Kannazuka, and Yashiori Island in Inazuma.
Trigger condition:
No clear trigger conditions for this quest. If all the requirements are met, find and defeat all the opponents from "Iwakura Art" Clan throughout Inazuma to complete the quest.
Quest Info:
After completing the prerequisite quest and unlocking all Statues of The Seven on corresponding islands, find and defeat all the samurai from "Iwakura Art" Clan throughout Inazuma.
Note:
①: If you arrive at the location and do not find the corresponding opponent, the Traveler may have killed it while exploring Inazuma, so just jump to the next location.
②: Some locations can only be accessed by completing the world quest "Sacred Sakura Cleansing Ritual" to obtain the "Memento Lens" and solving the puzzle to activate the teleport waypoint inside the underwater ruins of Araumi.
③: No order required for the first 5 samurai opponents, but it is recommended to follow my order to avoid omissions.
All target locations are shown on the map below:

Steps:
1. Defeat 5 samurai opponents of "Iwakura Art" Clan
①Go directly from the teleport waypoint near the Inazuma Fishing Association outside Inazuma City. Defeat the nearby samurai of the Iwakura Art, and then the chest will appear.

②Teleport to the waypoint on the mountain northeast of Jakotsu Mine. Head to the indicated location on the map to clear up the samurai in the mountaintop camp.

③Teleport to the easternmost waypoint on Watatsumi Island. Follow the arrows to the marked location (the left four-leaf clover on the map). Glide through the Phase Gate to Fort Mumei (the right four-leaf clover), and then glide southeast of the map to clear up the samurai on Fort Mumei Island.

④Teleport to the waypoint on the mountain south of Tatarasuna. Follow the arrows to the cave entrance, head into the cave, climb up the cave wall, and clear up the samurai in the camp.

⑤Teleport to the underwater waypoint of Araumi. Head to the indicated location on the map, and clear up the samurai near the shipwreck.

2. Teleport to the Kujou Encampment Waypoint.
Head to the indicated location on the map and talk to Iwakura Mitsunari at the top of the mountain. Adjust the game time to the next day, talk to him again and finish the dialogue to clear up the samurai.

3. Return to the north of the teleport waypoint outside Inazuma City.
After defeating all the samurai at the above locations, return to the north of the teleport waypoint outside Inazuma City and talk to any opponent of "Iwakura Art" Clan.

4. Defeat the last two opponents.
After the dialogue, defeat the last two opponents of "Iwakura Art" Clan to get their blades, as well as the achievement "Iwakura Out".

5. Insert the two blades into the Blade Mound to obtain the final Luxurious Chest.

Summary:
This is a hidden quest without guidance throughout the whole process. I suggest you follow the locations in this guide and play it through to check if there is any omission.
Follow-up/Parallel quest: "The Ill-Starred Legacy of Iwakura"
Collection Skip: Inazuma Hidden Quest Collection

