Speak to Ploh Trishbahk outside Castle Adoulin and select a necklace as your reward.
Warning: do not drop this necklace. If you do, you cannot complete Seekers of Adoulin Mission 4-28: Anagnorisis. There is no known way to retrieve the necklace at this time other than using the one-time-only item restore feature granted by GMs.
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