You point the machine at a place on the ground which you can see within view. Upon activation, an obfuscating black mist (heavily obscuring) permeates the area with a radius of 75 feet, unremovable by wind. The cloud spreads around corners. When a creature enters the black mist for the first time or starts its turn in the mist, they must make a CON saving throw or take 12d12 necrotic damage. They take half as much on a failed throw.   The plant life or ground in the area becomes covered with a black sludge, making the terrain that the mist covers difficult terrain.   If a creature dies in the mist, their soul is sucked into the machine. For each soul contained in the machine, add an additional d12 of damage whenever it is used. If a use of the machine fails to capture any souls, all souls contained in the machine are released.