Creeping Death

When you use an action to remove the stopper, a
cloud of thick ink pours out in a 20 foot radius,
spreads around corners and lasts for one minute.
The area is heavily obscured. Any creature who
starts it's turn in the cloud must make a DC 14
Constitution saving throw. On a failed save, a
creature takes 1d8 necrotic damage, or half as
much damage on a successful save. A medium
wind (11-20mph) can disperse the cloud after
3 rounds, or a strong wind (21+ mph) after 1.