Serpent venom
Injury poison dealing 10 (3d6) poison damage on DC 11 Constitution save, half on success. Coats weapons, ammunition, and trap components until delivered through a piercing or slash...
This poison must be harvested from a dead or incapacitated giant poisonous snake. A creature subjected to this poison must succeed on a DC 11 Constitution saving throw, taking 10 (3d6) poison damage on a failed save, or half as much damage on a successful one.
Injury. Injury poison can be applied to weapons, ammunition, trap components, and other objects that deal piercing or slashing damage and remains potent until delivered through a wound or washed off. A creature that takes piercing or slashing damage from an object coated with the poison is exposed to its effects.
Cost: 200 gp