Seventh Samurai quest is available after completing the Tatara Tales questline. Go to the island to the right of Inazuma City and talk to Xavier. Placing the flowers at the tombstones just gives you an achievement.

It seems that the achievement has been fixed, as I just logged on today, and suddenly had "They Shall Not Grow Old" unlocked.

i thought the 7th tomb is the one where that samurai died in fate of a fighter quest

If you place the 6 flower a new quest will appear at Nazuchi Beach (big wrecked ship) after server reset.

No, the 6 sword came from playing with tanuki near them

After give 6 location, I think we can claim box at this location at Higi Village, there box locked with 6 swords

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Island in the south of Jakotsu Mine anyone?

There are probably gonna be more tombstones as the Inazuma islands get released, otherwise it's just bugged

Apparently if you didn't collect them in one sitting it'll bug, so yeah, there are 6

I already found the 7 tombstones(the 6 in the guide and the other one down the higi village) but I didn't get any achievement.
It's either bugged or maybe there's an 8th tombstone?

bugged

Has anyone mentioned the one in the underground under serpents head?

https://gyazo.com/0128ca4f8561bfdd5a4f92c2d47fbd9d

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I think this tomb might relate to the Seven Samurai world quest

I've been to all 6 multiple times and got nothing, either bugged for some or there is 7th grave

There are a total of 6 tombs if you them you will get the achievement "they shall not grow old"

Last one is tucked in the cliff face on the beach directly west of Higi Village

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One more here but not the last, we are missing one I think, I saw people say there are 7, I'll keep looking for the last one

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How many graves total? I have found the 5 mentioned here but doesn't appear to be enough for the achievement.

could u pls post ss of all locations as im only missing 1

it shows u an archievement

"They Shall not Grow Old" when u find all of them

I've got another one

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And one more here, under the waypoint, hidden in the bushes

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There's one more here

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