Engulfing Smoke

You create a 20 foot radius sphere of suffocating fumes and smoke at a point you can see within 60 feet of you, the smoke heavily obscures the area and goes around corners.

If a creature starts or ends it’s turn or movement in the smoke, it must succeed on a Constitution saving throw or begin coughing until it starts or ends it’s turn outside of the smoke, a creature that doesn’t need to breath succeeds the save automatically. While a creature is coughing it is incapacitated and cannot breath, taking 2d8 necrotic damage at the start of each of its turns until it stops coughing.