The Arachnus Heavy Lascannon Battery was a Laser Weapon system that was used by the ancient Deredeo Pattern Dreadnoughts of the Legiones Astartes during the Great Crusade and Horus Heresy eras. The Arachnus Heavy Lascannon Battery was a set of two massive, twin-linked Lascannons, taking up both the Deredeo's weapon mounts.
Far more powerful than any other pattern of Lascannon regularly fielded by the Legiones Astartes, the Arachnus could inflict devastating amounts of damage with each hit, far more than any standard Las-weaponry. The Arachnus Heavy Lascannon Battery is still found in use by the various Space Marine Chapters and possibly the Traitor Legions that still maintain functioning Deredeo Dreadnoughts in the 41st Millennium.
- Forge World Webstore - Arachnus Heavy Lascannon Battery
- Imperial Armour Index: Forces of the Adeptus Astartes (8th Edition), pg. 29
- The Horus Heresy: Legiones Astartes - Age of Darkness Army List pp. 11, 78-79