Heartache Locket (5e Equipment)
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Wondrous item, rare
This heart-shaped necklace has a ruby gem locket on its end. While a creature is wearing this locket, they become made aware if anyone else wearing an identical locket is in deadly danger. For clarification, these are always found or made in a set, and don't work with other lockets not made at the same time as it (at the DM's discretion, there may be some way of connecting different heartache lockets, allowing some expansion to the set). When any creature wearing one of a set of these falls unconscious at 0 hit points or dies (whichever comes first), the ruby of every heartache locket in the set begins to glow a bright red glow that darkens slightly before lighting up again in a pattern of the individual wearer's heartbeat, and also warms up to a noticeable amount. This effect occurs regardless of where the wearers are, even across planes. The gem then emits red bright light in a 5-foot radius from the wearer, and dim light for another 5 feet. The glow and warmth lasts an hour until all necklaces stop glowing, though they are reusable and end early if all wearers recover to at least 1 hit point. Finally, all of the necklaces have the Unbreakable minor property, making it impossible to do something to the wearer that prevents the effect from occurring, except for using a wish to destroy the locket before killing the wearer.