Our group will use “Spyder” fishing line. In 15 or 30 lb test it will be used to trigger different alarms. The first type of alarm is a bag of cans/bottles with gravel inside. The fishing line is almost invisible. Second alarms are pits with punjii sticks. After that comes the stuff to knock people down. 12volt lights with motion sensors are around the buildings pointing out.
and 2 75lb dogs!!