Create Poison

You imbue one weapon that deals piercing or slashing damage, or up to ten pieces of ammunition with a deadly poison that retains its potency for the duration. The next time the weapon or ammunition piece is used to make an attack, on a hit, the weapon deals an extra 3d6 poison damage and the creature hit with the attack must make a Constitution saving throw or be poisoned for 1 minute. Once the affected weapon or ammunition is used to make an attack, the spell ends for that weapon or piece of ammunition.

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the poison damage increases by 1d6 for each slot above 2nd.