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I recently received Phlegethon's Trousers from Valkurm Dunes treasure casket, and my friend also wants a pair. My question is, could I help them farm for brown caskets and get them a pair if I already have one in my inventory? Or would it not show up in any brown box because I'm in the party and have one in possession?

Please let me know if anyone has had a similar experience and knows the answer or some educated guesses/logic would be appreciated too ^^