Wyvernstinger Scabbard (Patreon)

Wondrous item, uncommon

When you draw a sword from this magic scabbard, you can choose to speak its command word to coat the sword in a special poison (no action required). The first creature hit with that weapon within 1 minute must make a DC 13 Constitution saving throw. On a failed save, the creature takes 4d6 poison damage and is poisoned until the end of its next turn. On a success, the creature takes half as much poison damage and isn't poisoned. Once the scabbard is used to coat a sword in this way, it can't do so again until the next dawn.

"What good is honor to a dead man? When you draw your sword, make the first swing count; pull out whatever dirty trick it takes for you to come out on top. Save your rules for the tourneys."