A force weapon is a psychically attuned melee arm that a trained psyker can charge with the raw energy of the mind, transforming an ordinary-looking blade, staff, or hammer into a conduit of lethal power. Superficially similar to a power sword, a force weapon conceals a crystalline matrix that stores and channels psychic force, so that when its wielder wills it, a single strike can unmake flesh, spirit, and even immaterial entities that mundane weapons cannot harm.
In the hands of an ordinary warrior such a weapon is merely a well-made blade, for its true might depends wholly on the psyker who bears it. When empowered, it can slay daemons, banish creatures of the warp, and cut down enemy champions whose bodies would shrug off lesser strikes. This makes force weapons invaluable to the psychic warriors of the Imperium and beyond.
They come in many forms, including swords, axes, staves, and halberds, and are often exquisite works of craft, inscribed with wards and set with focusing gems. The librarians of the Space Marines carry them as marks of rank and instruments of war, while psykers of many other factions field their own equivalents. A force weapon is at once a duelling arm, a ritual focus, and a shield against the horrors of the immaterium.