Choking Smog

An insidious smog creeps into the target's airways, forcing them to cough. Choose a creature you can see within range. The target must succeed on a Constitution saving throw. The creature takes 2d6 poison damage and becomes poisoned for the duration on a failed save. On a successful save, the creature takes half as much damage, is not poisoned and the spell ends for it. While poisoned in this way, the creature coughs and wheezes violently, and is unable to speak intelligibly or cast spells that include a verbal component. And the end of the poisoned creature's turn, it must repeat the initial saving throw with the same effects.