The stinky Staff

You channel the putrid power stored within the staff into a devastating strike. Make a 1d10 melee spell attack against a creature within 10 feet.

If the attack deals damage, it deal an extra damage roll of Necrotic damage. The target must succeed on a COS saving throw or be affected by the poisoned condition until the end of your next turn.

Cantrip Upgrade. The damage die changes when you reach levels 5 (2d10), 11 (3d10), and 17 (4d10).