A Cerastus Knight-Acheron is an Imperial Knight pattern that is utilised exclusively for terror and shock assaults. The devastation wrought by Knights-Acheron is terrifying to behold. Armed with a fearsome Reaper Chainfist, twin-linked Heavy Bolters and an Acheron pattern Flame Cannon, they are employed as weapons of extermination and to inspire fear in their foes. Nothing will sway their attack until the enemy is utterly crushed, never to rise again from the flame-scoured ruins of their strongholds.
The Cerastus Knight-Acheron is a fearsome sight on the battlefield, a reaper of lives carefully designed not only to destroy, but also to inspire terror both in appearance and the manner in which it undertakes its grim task. The presence of an Acheron mark armour in the battlelines of a Household warns the foe to expect no mercy, for such weapons are only deployed for missions of extermination, to topple the works of the enemy and scour clean his lands with flame. Scions rarely choose to ride into battle in Acheron armour voluntarily, accepting the task instead as an arduous duty to be undertaken for the good of the House, for the anima of these armours are often awash in the inherited memories of massacres and slaughters uncounted. Those few scions who prefer such grim mounts are either warriors of iron will, capable of suppressing the sinister whispers of the armour's machine spirits, or tortured souls who relish the armour's malicious impulses and the carnage it wreaks on the field of battle.
- The Horus Heresy - Book Four: Conquest, by Alan Bligh, pp. 104, 125, 173, 296, 307
- The Horus Heresy - Book Five: Tempest by Alan Bligh, pp. 128-129
- Forge World - Cerastus Knight-Acheron