If you give Dendrobium to 6 Simple Tomb in Yashiori Island, you will get "They Shall Not Grow Old" achievement

Here are the locations of all the tombs

Route 1

Route 2

First, jump this cliff (you'll see some trees below you)

The tomb are located behind this bushes

Give the dendrobium

Route 3

Enter this hole

Route 4

Jump down from the cliff to the beach

Route 5

Route 6

If you need Dendrobium, I also made the farming routes guide here [Click Me]

My Guides Archive [Click Me]

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In-Depth - Thorough - Clean

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And that's it! I truly hope you find this guide useful

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