1) A knife. Stainless steel, but plastic will do in a pinch.
2) A flag. Black is scariest. Maybe that New Zealand one.
3) A camera phone. At least 6 pixel sensor resolution – grainy but not too grainy.
4) A victim. NB doesn’t have to be a human, could be something abstract, like freedom or Australian values e.g. mate-ship

See from 2:17