A Null Field Matrix is a form of advanced Necron technology used to project a large anti-psychic field around itself, similar to that employed on a smaller scale by Gloom Prisms and the Nightshroud barriers created by Monolith phalanxes and Gauss Pylon networks. Most commonly used to shield Necron Tomb Worlds from psychic disturbance, they display the Necron’s mastery over technology and their ability to create a technological defence for nearly any threat that they encounter.