Weight: 1 lb.
Estimated Value (Sane Cost Guide): 250,000 gp
DMG Value: 50,001+ gp
Geryon's Sting is a powerful magical item that can only be obtained by killing the devil Geryon and harvesting his stinger. To create this dagger, the stinger needs to be magically fashioned into a blade, during a midnight ritual involving a high level caster.
While wielding this dagger, you have advantage on saving throws against poison, and you have resistance against poison damage.
In addition, you gain a +3 bonus to attack and damage rolls made with this magic weapon. You can use a bonus to cause thick, black poison to coat the blade. The poison remains for 1 minute or until an attack using this weapon hits a creature. That creature must succeed on a DC 15 Constitution saving throw or take 2d10 poison damage and become poisoned for 1 minute. The dagger has 3 charges, all of which are recharged at dawn.
Note: Geryon's Sting is a powerful magic item, that should only be given to powerful characters. As such, this charm should only be awarded to a high level party that has defeated the powerful devil Geryon.