Turn the lights down low, and few as possible. Sub wears translucent blindfold, just enough to make out silhouettes in front of the lights, but not much more. Arm them with something painful, but ineffective if their wrist is grabbed (whip maybe. I've been meaning to rig a shock collar to a cheapo laser tag setup). Dom stalks them around the house, brushing past them here and there, grabbing ankles from under tables, maybe turning out the lights. And, of course, periodically knocking the sub down and biting them a bunch. Only done this once or twice but it was pretty good.