Stone of the Buyer (5e Equipment)
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Wondrous Item, very rare
It looks like a shiny stone, with a slightly gold tinge. But it's got much more than that! As an action, you can speak the command word to teleport to the Plane of the Buyer's Market (5e Environment), where anything and everything a buyer might want can be found, and even bought in bulk! Once you use this stone to teleport, it disappears forever.