Double Fanged Ring (5e Equipment)
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Ring, rare (requires attunement)
This enchanted ring has 5 charges and it regains all expended charges daily at dawn. Whenever you hit an enemy with a weapon attack, you may expend a charge to force the target to make a DC 15 Constitution saving throw or take 4d6 poison damage. If the ring ever drops to 0 charges, roll a 4 sided die. On the roll of 1, the ring disintegrates into a cloud of poisonous gas that is 5 feet in diameter. All creatures who enter or start their turn in the cloud are poisoned for 1d4 hours. Damage caused by the Double Fanged Ring cannot be reduced in any way, and it still deals half damage to creatures with immunity to poison damage.
When a creature makes a successful saving throw against this ring's effect, the wearer of the ring takes 4d6 poison damage.