The Hexrifle is another one of those bizarre Eldar weapons. Hexrifles are Dark Eldar weapons used primarily by Haemonculi and their pet minions that uses crystal cylinders that contain a tiny amount of the Glass Plague virus. Crystalline cylinders containing the tiniest quantity of the disease are fired from the rifles, shattering upon impact and exposing the target to the plague. The virus spreads incredibly fast on contact with flesh, turning the victim into a glass statue. More often then not, the particular Dark Eldar would shout, "Strike a Pose!" before adding the victim as part of their collection. How a virus can rearrange the molecular structure of a carbon based lifeform into silicon is unknown, with the only explanation without going into supernatural means is through techno-babble/Webway-physics bullshit.
The Plague of Glass had once afflicted the Dark City in the 36th Millennium. While the plague itself has long since been stopped, samples of the disease still exist in phials within the laboratories of Haemonculi, to employ as a weapon against their enemies. Each Hexrifle is unique, created for an individual Haemonculus to deliver this potent and exotic plague in battle, but all function in essentially the same way.
Unfortunately, despite the cool/weird fluff written down, on the tabletop, the Hexrifle is just a bog-standard Sniper Rifle now. It can shoot at characters and has a tiny chance of inflicting a mortal wound in addition to normal damage. The weapon had a unique rule when it was introduced where it had a chance to insta-kill its target on a lucky dice roll, but not anymore! The fact that both the Acothyst and the Haemonculus like to get close and dirty in melee and not stand back and fire Heavy weapons further hurts the potential of this weapon.