Toxic Breath

You exhale a cloud of misty vapor in a 30-foot cone in front of you. Each creature within the cone must make a Constitution saving throw. On a failure, creatures take 8d6 poison damage, and become poisoned until the start of your next turn. While poisoned in this way, a creature's speed is reduced by half. On a successful save, creatures take half damage, are not poisoned, and do not have their speed reduced.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot above 3rd.