My hair prickled at your description - I'm completely enthralled! A void, such as one left by anti-matter? Creatures comprised of localized anti-matter! That would explain the mist as morphic resonance. Kept in an invisible status field, projected telepathically into the minds of their victims, just before they attack. When you say occult items, I'm not sure what you mean, but what comes to mind is a variation of a portable extrapolator shield mechanism.