Asphyx Shells were weapons used by the Thousand Sons.[1]
Tainted with a psycho-reactive toxin of unknown origins, the Thousand Sons were able to arm their elites with these unusual and highly lethal munitions. These shells were first believed to have been developed on Prospero for use with relatively primitive projectile weapons made to defend against the Psychneuein, but the difficulties of mass production and scaling of their effect limited their deployment.[1]
See also
Sources
- 1: The Horus Heresy Book Seven - Inferno, pg. 210