It's said that it once belonged to Koshei the Deathless, the curious. Provides 2 squares of weak green light. Most keep it as the death protection is valuable because not many items have it without having a limited amount of charges.
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After delivering the 4 broken amulet pieces to A Sweaty Cyclops, you can collect Koshei's Ancient Amulet from A Sweaty Cyclops after a 24-hour (real-time) wait. You must use it on Koshei's dead body in order to defeat him, but you can also just sell it for the same price as or sometimes even higher than the Blue Legs, the reward of the quest, to other players. Part of Koshei the Deathless Quest.