When manythings detects motion, scare the intruder.
When manythings detects motion, have it switch on a device that rarely gets switched on by itself. For example, I have the motion switch on one of my lamps that I always turn as with a group. I never turn on the light by itself so it is the perfect switch. Then when the light gets switched on; have your lights, sounds, speakers, etc. react to that light being switched on.