Montree1 you will find the berries in a chest or something once you go deeper into the cave. I'm at around floor 56 and I have seen about 4-6 of them so far. To take it out of the cave with you though, you will need the Transmute spell which allows you to transform any non-artifact item you want into an artifact item, allowing you to take it out of them cave with you and keep it. Do this with the berries and bring it to him.
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 "The Enchanted Cave 2"){kind=icon}
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