Stone Grenade (5e Equipment)
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Wondrous item, common
This magic rock appears indistinguishable from a normal stone, but has in fact been infused with unstable magic. As an action, you can speak the stone's command word and throw it at a point up to 60 feet away. The stone then explodes.
Each creature within 15 feet of an exploding stone grenade must make a DC 15 Dexterity saving throw, taking 3d6 piercing damage on a failed save, or half as much on a successful save.
You can determine a grenade's command word by spending 10 minutes focusing on it, or via the identify spell.