Force weapons

Force weapons are advanced, psychically-attuned close combat weapons that are only fully effective in the hands of a psyker. Force weapons effectively act as deadly, psychic extensions of the wielder's own powers. They are designed to allow a psyker to channel deadly Ether energies into their victim, acting as a conduit between the wielder's mind and the flesh of his target.
Large alien monstrosities and daemons that are resilient to conventional weapons can be slain outright by a single wound, as their bodies and minds are destroyed by the unearthly powers of the Immaterium.
Force weapons take the form of swords, spears or other close combat weapons. Within the structure of the weapon is interwoven a powerful psi-convector, formed into a precise serpentine shape which concentrates and directs psychic energy. This sometimes appears as a pattern on the blade. If a non-psyker takes up such a weapon it functions as a standard weapon.