Amulet of the Undying

This is a metallic amulet whose centerpiece is a red gem, caved into the shape of a skull, if a creature holds the amulet up to their ear, they hear quiet incoherent whispering.

The amulet is linked to the life forces of the creatures it is attuned to, if more than half of the creatures it is attuned to die, the skull shaped gem shatters, rewinding time to 6 hours before the last person died.

Once the skull shaped gem has shattered, the amulet is worthless and holds no magical power.

To attune to the amulet, each creature must place a drop of their blood on the mouth of the skull, which is absorbed by the gemstone.  

Notes: ritual that allows up to 8 creatures to bind their life force to it