At the touch of the sphere the purple mist had dissolved.

Beyond, more purple and green mist roiled in a shapeless tunnel.

Above them, perhaps a hundred feet in the air, was a huge ball of purple mist, radiating light like an otherwordly sun.

Once again, purple mist boiled out of the glowing rectangle on the wall.

Apparently creeping toward him was a faint, ever-brightening purple mist.

Die alone and forlorn in the cold purple mists.

Absently, he noted that the purple mist and arms had vanished.

Through the shrouds of purple mist, the passing mother ship was visible.

The purple mist had something to do with the alectors - perhaps their Tables?

Once there, they learn that Greede's citizens are being poisoned by a purple mist.