Guardian Gem
Wondrous item (uncommon)
This midnight and sepia gemstone was enchanted with powerful protective magic by the Mortal Guardians’ most talented mages. Once activated by a guild member, it grants special boons to the Mortal Guardian and their nearby allies. As a bonus action, you may shatter the guardian gem and release its power. Up to six creatures of your choice within 60 feet of you gain temporary hit points equal to half their hit point maximum. The temporary hit points last for one minute, and while a creature has these temporary hit points, once per turn when the creature deals damage they deal 1d8 additional radiant damage.
If a creature that is not a member of the Mortal Guardians attempts to use the gem, it fractures and releases a blinding surge of luminescent energy. Each creature within 15 feet of the gem and not behind total cover must make a DC 16 Constitution saving throw or be blinded until the end of its next turn.