An Eclipse Missile, officially designated an Eclipse Pattern Missile, was a specialised class of Imperial missile utilised solely by the Raven Guard Legion, primarily during the Great Crusade and Horus Heresy eras of the late 30th and early 31st Millennia. It is unknown if the weapons are still deployed in the late 41st Millennium.
The Eclipse warheads used on the missiles differed from others in that rather than causing outright destruction they were designed to sow confusion and break-up enemy defences in preparation for the Raven Guard Legion's lethal strike. In addition to explosive charges, the warheads combined concussion charges with clouds of chemical smoke, confusing and blinding the enemy.
- The Horus Heresy: Legiones Astartes - Isstvan Campaign Legions, pp. 108
- The Horus Heresy: Book Three - Extermination (Forge World Series) by Alan Bligh, pg. 278