My Idea is called the Damning Tormentor, it works like this:
It is a small ball, the size of a Baseball or Tennis ball, made out of Onyx.
You throw it like you would a grenade. All within the radius (about 3 meters) will have their souls painfully ripped from their bodies and sucked into the sphere. Once there, they are put through tortures designed to drive them insane with one purpose; when the ball is thrown in it's secondary form (by pressing a button shaped like the Ghostbusters' insignia)they are released, at which time they do everything in their power to kill everyone within a zone, which is a 2-meter radius orb that increases it's radius by 2 meters for every soul that is in the weapon. After all living beings within the area are dead, the souls are released and sent on their merry way into the afterlife. Then, you can pick up the orb and use again.