Venomous Strike

As part of the action used to cast this spell, you imbue a magical poison on a weapon or piece of ammo you touch and must make an attack with a it against one creature within the weapon's range, otherwise the spell fails. On a hit, the target suffers the attack's normal effects plus 1d4 poison damage. If your attack roll is a critical hit, the target becomes poisoned until the end of its next turn. Targets resistant or immune to poison damage or immune to the poisoned condition do not become poisoned.

This spell deals an additional 1d4 poison damage when you reach 5th level (2d4), 11th level (3d4) and 17th level (4d4).